Looking at some statistics my feeling with this regard is that updating the FAQ and discussing it is simply just causing a needle in a haystack problem. Why?
There are at the time of writing this answer 98110 questions on Super User. Of that there are 1265 tagged software-rec. At the moment only 156 of these are closed.
We are talking about less then 2% of all questions asked on Super User after 2 years of existence. Apart from the once in a while Meta post about a question being closed and asking why, in general, we spend less then 0.02% of your time having to deal with these question, closed or not.
As already pointed out, if the question is well asked, is about How to do something that involves a software recommendation and is not asking to compare features or find out what is the best software, these question are acceptable as long as they solve an actual problem.
In cases where they are not, they will be closed, either by the community moderators, or the diamond moderators if flagged.
The problem with recommendation that are the best of or comparing features with regards to software is the following:
- They are asked by drive-by users that will never come back
- They are asked by users that want to have a debate about it.
- They are legitimate questions to solve a problem, asked the wrong way.
The latter, as already pointed out, can be fixed.
In short, to be honest, I don't see the problem. Looking at the bigger picture the amount of time spent on the issue doesn't quantity the amount of questions it will affect.
Beyond that, it is already covered in the FAQ, and since each SE has a different topic, each site has it's own interpretation defined in each child meta.