Before doing this, I like to look at what might have been lost. The following 133 tags have been created by users with < 1500 reputation at the time of creation during the past 365 days and are currently in-use on at least 2 questions:
Name Used User Created RepOnCreation
------------------------ ---- ------------------- ---------- -------------
sublime-text-3 90 Kriem 7/22/2013 404
windows-8.1-upgrade 90 Joey Adams 10/19/2013 658
sublime-text 42 Lohoris 9/13/2013 701
chromecast 35 Raj More 10/4/2013 515
ubuntu-13.10 33 Vladimir Oselsky 1/2/2014 332
google-chrome-devtools 31 MoonSire 11/12/2013 442
dos 23 SofaKng 1/22/2014 327
fedora-19 20 wullxz 9/11/2013 1217
smime 17 DeepSpace101 8/1/2013 538
fedora-20 16 ChocoDeveloper 3/1/2014 739
raspbian 15 Bart van Heukelom 5/8/2014 882
xfce4 14 lang2 9/24/2013 436
microsoft-surface-pro 13 Matt Clark 11/5/2013 304
libvirt 12 mavit 9/27/2013 310
iis-8 11 Feroc 8/14/2013 345
xenserver 11 Alex 11/6/2013 339
unresponsive 11 Mike Pateras 11/3/2013 356
firefox-developer-tools 10 MoonSire 11/12/2013 444
mariadb 10 mickburkejnr 8/3/2013 730
window-8 10 curious_kid 12/28/2013 342
remoteapp 9 damryfbfnetsi 1/14/2014 364
downloading 9 broiyan 11/7/2013 357
index 8 Martin Prikryl 4/7/2014 932
sfc 7 galacticninja 12/29/2013 1423
for-loop 7 Kirstin 12/5/2013 1018
cmake 7 Chen Levy 8/13/2013 645
font-smoothing 6 Robert Koritnik 9/3/2013 468
tampermonkey 6 Brock Adams 2/6/2014 672
pycharm 6 Anthony Kong 2/26/2014 401
traktor 6 Franck Dernoncourt 4/6/2014 513
search-indexing 6 Flak DiNenno 4/8/2014 594
reference 5 Ian McClellan 3/12/2014 300
mapped-drive 5 GSerg 3/27/2014 388
beaglebone 5 Krumelur 4/1/2014 343
hiren 5 rossmcm 9/15/2013 391
sata-to-usb 5 soul 9/29/2013 1314
pgadmin3 5 Eric Leschinski 8/10/2013 499
whatsapp 5 Antony Lee 8/4/2013 340
sccm 5 Myrddin Emrys 11/26/2013 1006
internet-explorer-dev 5 MoonSire 11/12/2013 462
html-mail 5 Camilo Martin 10/22/2013 619
hangouts 4 Ash 10/16/2013 829
bonding 4 Nemoden 11/6/2013 356
quod-libet 4 unor 11/21/2013 578
windows-features 4 Brian Lacy 12/17/2013 746
mpeg2 4 Eli 7/25/2013 431
vb6 4 nate 10/9/2013 492
gridengine 4 gojira 10/10/2013 592
windirstat 4 Josh R 9/10/2013 737
fontforge 4 Eliptical View 1/20/2014 333
cmder 4 Zsolt Botykai 1/16/2014 399
omnibox 4 D.Iankov 4/16/2014 1471
elementaryos 4 Deniz Zoeteman 4/28/2014 397
oracle-linux 4 Simkill 5/8/2014 1224
autologon 3 Colyn1337 4/28/2014 622
parted 3 wiak 5/2/2014 375
superputty 3 Franck Dernoncourt 6/15/2014 691
atlassian 3 Unnikrishnan 4/17/2014 601
lftp 3 wiak 4/16/2014 365
displayfusion 3 Franck Dernoncourt 3/21/2014 493
offlineimap 3 winchendonsprings 1/8/2014 457
evil 3 progo 1/16/2014 379
opensuse-13.1 3 djechelon 2/7/2014 1275
ffserver 3 Yasser Zamani 2/9/2014 583
lighttable 3 erikvold 2/26/2014 793
zorin 3 Zonder 3/6/2014 535
freeradius 3 Augustus Francis 3/13/2014 370
dax 3 Andi Mohr 9/27/2013 342
sparsefile 3 Michael Yasumoto 10/12/2013 385
difftool 3 Tiago Veloso 8/1/2013 897
remmina 3 Eric Leschinski 8/6/2013 474
icedove 3 l1zard 8/9/2013 508
adobe-audition 3 Lynda 8/14/2013 1218
shebang 3 Ole Tange 8/21/2013 595
clojure 3 golimar 8/28/2013 515
feature-regression 3 naxa 11/21/2013 1204
adobe-creative-cloud 3 damryfbfnetsi 1/7/2014 302
slate 3 Duijf 12/1/2013 559
config-files 3 thejh 12/4/2013 405
apt-cache 3 Peter Westlake 10/30/2013 526
badbios 3 Ash 11/4/2013 965
radvd 3 Dolda2000 10/20/2013 355
mogrify 2 wim 10/23/2013 522
mime-headers 2 Frank 10/28/2013 454
rj-11 2 Ash 11/15/2013 1056
elevated 2 Langhard 12/5/2013 410
jmeter 2 TusharG 11/25/2013 695
lotus 2 Antony Lee 11/27/2013 540
stylish 2 Rookie 11/28/2013 363
pkcs 2 XXL 11/28/2013 738
lsusb 2 Jonathon Reinhart 1/7/2014 478
libusb 2 Jonathon Reinhart 1/7/2014 478
statsvn 2 smokris 12/6/2013 434
eraser 2 oscilatingcretin 12/8/2013 876
clearos 2 NitroxDM 8/28/2013 341
msklc 2 Lohoris 8/20/2013 738
iftop 2 Eric Leschinski 8/11/2013 499
elpa 2 Chen Levy 8/13/2013 645
awstats 2 JoshRibs 10/13/2013 443
psi 2 unor 10/2/2013 559
pipelining 2 Maxim V. Pavlov 10/4/2013 319
tcpreplay 2 vpram86 9/26/2013 1105
tarsnap 2 Avery Chan 3/21/2014 753
smb2 2 Alexander Gladysh 3/12/2014 311
ipkg 2 Alexander Gladysh 3/12/2014 311
udisks 2 Envite 4/3/2014 350
eap-mschapv2 2 Adambean 3/31/2014 496
network-policy-server 2 Adambean 3/31/2014 496
keyremap4macbook 2 Peeja 3/10/2014 346
octopress 2 Anthony Kong 3/2/2014 406
moinmoin 2 lorenzog 2/26/2014 1106
logcheck 2 Eddie Parker 2/12/2014 331
surface-2 2 Ben Johnson mk2 1/24/2014 640
office-on-demand 2 damryfbfnetsi 1/28/2014 390
sata-cable 2 Sickest 2/4/2014 742
braces 2 java.is.for.desktop 1/16/2014 435
icicles 2 Drew 1/16/2014 623
terminal-multiplexer 2 shinokada 12/31/2013 307
ssis 2 Andi Mohr 1/15/2014 551
sqoop 2 P.Brian.Mackey 4/7/2014 679
nconvert 2 wiak 4/17/2014 365
memory-speed 2 yosh m 4/9/2014 1133
p2v 2 user1301428 4/17/2014 1413
answerfile 2 Colyn1337 4/28/2014 622
noip 2 einpoklum 5/9/2014 318
msiexec 2 Stefano Borini 6/6/2014 582
system-notification-area 2 Edward Brey 6/7/2014 445
texmaker 2 Franck Dernoncourt 6/15/2014 703
usbip 2 davidbaumann 6/17/2014 873
smart-tv 2 PHPst 6/30/2014 554
append 2 nmuntz 7/2/2014 497
centos-7 2 Rob 7/10/2014 373
google-chrome-canary 2 Shimmy 5/6/2014 433
For contrast, users with >= 1500 reputation created the following 93 tags (again, only those in use on at least 2 questions):
Name Used User Created RepOnCreation
------------------------- ---- ---------------- ---------- -------------
cmd.exe 264 slhck 8/28/2013 62885
onedrive 199 tombull89 1/27/2014 4827
windows-server-2012-r2 67 soandos 8/7/2013 14810
hp-elitebook 65 DragonLord 7/27/2013 8319
visual-studio-2013 57 Ƭᴇcʜιᴇ007 9/20/2013 37956
kali-linux 55 tapped-out 8/4/2013 2537
ubuntu-14.04 51 Devid 3/31/2014 1906
heartbleed 23 DragonLord 4/8/2014 10340
email-filter 21 Breakthrough 7/1/2014 24324
preview.app 18 slhck 8/24/2013 62426
microsoft-powerpoint-2013 18 Paul 9/23/2013 22054
textmate-2 16 slhck 8/28/2013 62909
windows-8-refresh 16 Oliver Salzburg 3/19/2014 36867
weechat 14 tapped-out 9/2/2013 2709
cutepdf 14 wonea 9/24/2013 1579
file-filter 14 Breakthrough 7/2/2014 24324
windows-libraries 12 Darth Android 7/18/2013 19649
lpt 11 sammyg 8/4/2013 1690
resharper 11 wonea 9/25/2013 1585
powershell-ise 10 Iszi 8/12/2013 3167
citrix-receiver 10 wonea 9/7/2013 1528
docker 10 Oliver Salzburg 3/31/2014 37486
gitlab 10 Sathya 3/4/2014 35232
bittorrent-sync 9 Ilari Kajaste 11/22/2013 1853
footers 9 WilliamKF 9/17/2013 1692
bufferbloat 8 Kevin Panko 10/16/2013 2762
miracast 7 tombull89 9/27/2013 4630
av-receiver 7 wonea 9/7/2013 1528
powershell-4.0 7 Louis 11/23/2013 5583
icalendar 7 tapped-out 10/6/2013 2889
intellisense 7 AthomSfere 10/10/2013 4782
iperf 7 sammyg 11/1/2013 2273
windows-2012 7 PeanutsMonkey 3/11/2014 2034
zabbix 7 ekaj 1/8/2014 2151
tuleap 7 Sathya 5/28/2014 36008
4k-resolution 6 WilliamKF 6/4/2014 2034
tails 6 Daniel Beck 5/1/2014 58204
exchange-2013 6 ppumkin 4/3/2014 2341
serial-number 6 netvope 1/5/2014 1501
microsoft-access-2013 6 soandos 1/10/2014 15553
tiles 6 MatthewThepc 11/23/2013 2154
static 6 Ben Richards 12/6/2013 6504
widi 5 Pops 11/9/2013 3062
rdiff-backup 5 davidgo 12/28/2013 7297
mega 5 wonea 9/15/2013 1552
external-dvd 5 davidgo 8/17/2013 4678
sequel-pro 5 slhck 10/3/2013 65843
chocolatey 5 Julian Knight 5/29/2014 6010
osx-yosemite 4 slhck 6/4/2014 78824
tsv 4 Indrek 4/15/2014 12291
windows-embedded-8 4 Ƭᴇcʜιᴇ007 9/30/2013 38495
microsoft-excel-2000 4 wonea 9/26/2013 1585
dia 4 wonea 9/5/2013 1518
steam-os 4 Oliver Salzburg 12/14/2013 34329
guid 4 Synetech 12/20/2013 33862
roles 4 Keltari 12/2/2013 18089
multiarch 4 Vi. 12/5/2013 3842
clink 3 Charles Roper 12/5/2013 3844
qmail 3 Michael Kjörling 1/3/2014 6510
melt 3 slhck 1/10/2014 71506
brackets 3 Oliver Salzburg 3/19/2014 36867
worm-media 3 Kevin Panko 2/20/2014 3405
edible-ink-printing 3 rob 3/3/2014 8302
digikam 3 wonea 9/4/2013 1512
adobe-bridge 3 tapped-out 8/31/2013 2682
placeholder 3 Hennes 8/26/2013 24432
carddav 3 ridogi 8/27/2013 2185
metasploit 3 wonea 9/24/2013 1579
openscad 3 Kevin Panko 10/24/2013 2784
rsnapshot 3 lajuette 10/28/2013 3274
802.11ac 3 Evan Carroll 5/24/2014 1523
dm-crypt 3 Gilles 6/13/2014 29685
fusion-drive 3 slhck 6/25/2014 80066
google-compute-engine 2 slhck 6/25/2014 80102
zenoss 2 Oliver Salzburg 6/19/2014 39519
plex 2 BigHomie 5/26/2014 2800
can-bus 2 evan.bovie 5/3/2014 2157
magento 2 Brian Knoblauch 5/6/2014 2877
gdisk 2 Mikhail 4/21/2014 2126
rogue 2 Keltari 4/2/2014 20865
thrashing 2 endolith 11/1/2013 1640
windows-ics 2 tapped-out 10/6/2013 2889
karma 2 wonea 9/18/2013 1552
pcoip 2 Brian Knoblauch 8/15/2013 2702
megui 2 wonea 9/14/2013 1546
personal-block-list 2 Al E. 2/8/2014 2454
nexus-5 2 Nathan Long 1/4/2014 3256
block-device 2 davidgo 12/31/2013 7327
multics 2 Kevin Panko 12/4/2013 3028
robots.txt 2 Nicu Zecheru 12/10/2013 2872
hexchat 2 Chipperyman 11/21/2013 1533
faketime 2 terdon 10/14/2013 18370
ask-toolbar 2 ChrisF 11/24/2013 32141
During this same time period, 479 tags were destroyed, either because they were merged into another tag, weren't used on any questions, or because after 6 months they were only used on 1 question and had no tag wiki describing their intended use. It's not possible for me to determine who created them.
My recommendation:
Implementing this would be unwise at this time. Super User covers a large number of systems and products, many of which don't have tags. If we're going to further restrict the ability of folks to create new tags, those with the privilege need to be stepping up to create them when needed. Right now, that doesn't appear to be happening consistently: the majority of tags that end up being used more than once is done by users who would no longer be able to if we raised the privilege level.
Note that we recently implemented warnings for new tag creation - whether this will serve to slow the creation of unneeded tags remains to be seen.
Appendix: tags removed during the past 365 days
Here is a full list of tags removed during the last 365 days, for any reason. There are a total of 703 of these tags, which reflects both a different time period from that above (I'm adding this information a month or so later) and an improved method of scraping the log files for this data (don't use SQL when you need a regex):
1.2.5
1password
2003
4g
4k
aafp
aalib
accent
access
access
access-denied
access-denied
ach-linux
activation
activebatch
active-window
actor
actors
adb
adfind
aero-shake
airprint
airprint
akmod
altgr
amd-raidxpert
amule
android-recovery
apache-2.4.6
apache-openoffice
apache-solr
apk
appcmd
appledouble
application-switching
app-switching
apu
archey
archicad
archivemail
areca
arrow
audio-port
auditing
autodesk-animator
autodesk-sketchbookpro
auto-hide
autopager
awesome
ayiya
backup-sqldatabase
bah
batch-processing
beep
belvedere
billing
bing-bot
bitlord
blackscreen
blocked
blurred
bomgar
books
boolean-operators
bottom-posting
braille
brands
break
brew
business-catalyst
business-model
cacti
caja
calc
call-forwarding
can
canadian-luke
capacity
carp
case-sensitive
catalina
category
ccsvchst.exe
cde
cell-phone
centreon
cfosspeed
chiliproject
chiliproject
chiliproject
chksk
chrome-app-shortcut
chrome-canary
chrome-url
cleanup
client
close-application
cloudflare
collapse
colorfultabs
comfort
command
communication
compi
computer-forensics
configuration
configure
conflicts
conve
conversation
copy.com
core-dump
core-pattern
cost-efficiency
couchbase
cpumon
cronolog
cstates
ctrlp-plugin
currency-conversion
current
custom
customization
cwd
d
das
data-destruction
data-formatting
date-range
daylight-savings-time
ddl
debian-7
dect
default
default-browser
defender
delegation
deleting
desktop-mode
desktop-window-manager
desperation
details
detect
developer
developer-tools
development-environment
device-id
devices
dicom
dictconv
diehard
different
digital-frame
disable
disconnected
disk
disk-erasure
disposal
disqus
distcc
div
dmake
document-library
dos
dotnetnuke
downtime
dragon-dictate
drbd
drobo-5n
dschychronize
dsquery
dualboot
dual-boot
duplicate-files
dust
dvd-flick
dxtory
dynamo
e-bay
economics
edge
edible-printing
editpad
education
electricity
electricity
elementaryos
elluminate
email-formats
emoji
emp
endianess
entertainment
epic
errors
eucalyptus
excel-2000
excel-2010-mac
excel-for-mac
exchangeonline
excle
exe
executable
expand
extension-cable
external-antenna
external-card
facetime
failure
fat
feedgnuplot
fignore
file-dialog
filesystem-limits
find-and-run-robot
fireworks
flickering
f-lock
flyout
focuswriter
font-color
fontforge
foot-bullet
formatted
forward-seek
foxit
france
freebsd-install
freeswan
freetype
frustration
fsnotify
full-computer-name
full-hd
full-path
fuser
fusion
future
game-server
gauthenticator
ghostview
gigabit
ginn
git-daemon
gitstack
git-tfs
gns3
goldwave
google-app-launcher
google-hangout
google-reader
google-ultron
google-wallet
google-webmaster-tools
gphoto
gpo
grainy
group-polcy
groupware
guide
guidelines
h265
hack
hack
hack
haiku-os
haiku-os-pm
hash-table
hash-value
hdf
headless-ubuntu
help-vampire
help-vampire
hidden
hide
hide-window
hipchat
home
horizontal
hotplugging
hpf370
hsqldb
html-editor
human-insensitive
hwnd
hyphenation
icall
idea
idl
idle
idm
ieee1284
ifttt
illustrator
imessage
index
indirect-reference
information
initcwnd
insensitive
insertion-fault
insertion-loss
inst
install4j
instruction-register
intel-mic
intel-vt
intel-xeon
intensifypro
intermittent
internet-explorer-desktop
invalid-ip
invisible
iphone-5
ipmi
ise
jdownloader
jetty
js
keys
kget
kids
kmscon
lang
laptop-displayblackscreen
ldme
ld-preload
leak
legalnoticetext
libopus
libtermcap
licencing
lilypond
lines
link2sd
link-shell-extention
liveticker
lmde
locked
lockup
logo
loop
loop
lte
lucene
lucidchart
lycom
mac-filter
mac-hg
magento
magic
maildrop
malicious
mapping
marquee
matching
maximize
mdsn
megui
memory-address-register
memory-buffer-register
memory-data-register
menubar
menus
metro
metro-twit
micosoft-word-2010
micro-receiver
micro-sd
microsof-access
microsoft-exchange
microsoft-kb
microsoft-office-365
microsoft-office-xp
microsoft-outlook-2000
microsoft-outlook-forms
microsoft-photo-editor
microsoft-word-mac2011
microsost-word-2011
middle-mouse-button
middle-mouse-button
minimal-install
minimize
minimize
minitool
missing-dll
mkfs.vfat
mktemp
mockup
modi
mru
mtools
mtputty
multiarch
name
named-formula
nbd
neorouter
net
netiquette
network-block-device
network-design
network-policy-serverb
nofiles
non-printable
ns3
nsswitch
ntds
nucleus-rtos
nuevi
numactl
nut
nvida
objectdock
offline
offline
old-hardware
omr
on-board-raid
oncenote
online
online-resources
open-file-dialog
openfine
opengrok
opensearch
open-with
operations
operator
oracle-11g
oraclelinux
osc
.ost
ost2pst
outlook-data
outlook-mac
output
override
p910nd
packa
padding
paintbrush
paperport
parentheses
parentheses
pattern
pbs
pci-dss
pdc
pdf-xchange-viewer
pelican
pelican
pendactyl
photography
photoshop-cc
photostream
php-fpm
physicalpath
pi
pinterest
pinterest
piping
plc
plot
plotting
plugings
pny
polish
portfolio
porting
poster-printing
povray
powerline
powerpint
power-saving-mode
preload
prices
primary-zone
printer-drivers
printer-sharing
product-comparison
product-number
program
program-counter-register
programming
protel
prototype
proxycap
psb
psreadline
.pst
pty
pydev
qubes
quicksearch
quit
r61
raspian
rawtherapee
rcirc
reader
reading-pane
receiver
recurring
reddit
redhat-6.2
rednotebook
re-encapsulation
reformat
refresh
refresh
reliance
reload
remi-repository
requests
request-tracker
resin
respawn
retext
rfid
rich-snippet
rpm-spec
rssi
rst
safari-6
safari-webinspector
sar
sar
sato-printer
sbcl
scattergraph
sche
school
scientific-linux-6
scilab
screenpresso
sd
sdd
secure
security-camera
self-healing
server
server
server-side
shares
sharing
shim
shopping
signature-verification
simple-mapi
simulink
simultaneous
single-bit-error
skydrive
skype-manager
smartart
smartos
smbios
smtp-client
snagit
snapper
snapping
soft-link
sound
sourcetree
span
spdy
spec
spin-down
sqla
sql-anywhere
sql-azure
sqltools
ssdt
stability
start
start-button
starter
stata
state
stereo-mix
stmp
stop
subject
sublime
sublime
support
surface
surface
surface-pro-2
symbop
sync-center
system
system-defaults
system-hang
system-load
t
tagging
tamil
targetprocess
team-explorer
technology
telepathy
teradata
term
tesla
tesseract
textmate2
texworks
tf
thinkapd
tiemu
tiling
timeclock
timesheets
tkinter
tonido
topology
tos
total-copy
total-eclipse
tracert
tracking-protection-list
transformer
transplant
troff
ttcp
ufd
uhd
ultimate-edition
umdh
umsdos
unicorn
uniform-server
unlink
untagged
untagged
untagged
untagged
untagged
untagged
untagged
untagged
untagged
untagged
untagged
userchrome.css
utility
v2p
vcf
verify
verizon-wireless
vertical
vgaswitcheroo
video-drivers
videowall
vigor
vigor2920vn
vintage
virtual
virus-scanning
virustotal
virutalbox
visudo
vp9
vswitch
warning
watts
where
whited00r
whmcs
winclone
window-8
window-maker
window-management
windows-2008-r2
windows-8.1.1
windows-phone-emulator
windows-service-packs
windowsspeechrecognition
windows-virtual-pc
windwos
win-key
wodim
word-2011
word-2013
wp-mobile
x1
x2go
xcos
xfsm
xmlsec
xnest
xpages
x-raid2
yahoo-search
yakuake
yammer
zarafa
zeitgeist
zend-framework
zombie
zotac
[non-printable],[insertion-loss], and[delegation]. People should understand that new tags they add don't help others find their question faster if those tags don't address any experts in a certain field.