We just did a tag synonym reversal for [tag:osx] and [tag:macos].  The move was technically correct, but it's creating an unanticipated problem (at least for me, I'm just assuming some others are similarly affected).

[tag:osx] couldn't be confused with anything else.  The official names of the OS that contain "mac" have all been recognizable by capitalization and/or spacing: Mac OS, Mac OS X, macOS.

Both capitalization and spacing are lost in the [tag:macos] tag.  I keep misreading it as "macros".  I just spent several minutes unsuccessfully trying to add what I thought was a missing OS tag on a question.  [tag:osx] has been synonomized, but the system wouldn't add it because [tag:macos] was already there and I was misreading it as [tag:macros] (which was also relevant to the question).

A tag label doesn't need to be the official name, especially when there have been a lot of similar official names.  It can be an easily understandable placeholder label.  Since macOS has gone through so many name changes, people still think of it with various terms.  I'd like to suggest renaming the primary tag with a less mistakable label.  A few suggestions:

 - [tag:mac-os]
 - [tag:macos-osx]

Of course the wiki excerpt can clarify that the tag applies to any name version of the OS.

Note that people would not be expected to enter the full tag text of either suggestion.  In the second case, typing either of the familiar "macos" or "osx" would display the tag because each is a fragment.  The first suggestion would have the existing [tag:macos] and [tag:osx] synonomized, so typing the familiar tag name would produce the displayed tag.

It would be useful for people to weigh in on what the tag text should be.  My own thoughts are that while the addition of "osx" will add useful context, any version containing "macos" will be prone to misreading.  So [tag:mac-os] would be the least mistakable.  It would refer generically to any Mac operating system rather than a specific OS name.