In the beginning, RPG.SE was Community Wiki crazy. We used it for everything. We have an old Meta question on what to use CW for. But then we realized list questions were bad and CW was being used as a dumping ground for bad questions. So now CW is anathema. Some hunt down and kill old CW questions, annoying old users.
In 2012 I asked this question again, and the answer at the time was "lists and things about the future," but since then we've come down firmly on lists and things about the future being off-topic or, if tightly scoped, on topic but not CW, as well.
It was made a mod-only option in 2010, and the autoconvert to CW functionality was removed in 2014.
We still flirt with "well maybe, for a list question..."
Can we come up with modern guidance on how to use Community Wiki? It's fallen largely into disuse network-wide so "never" is legitimate, but we tend to just say "well... rare cases" which raises the question of what that rare case might look like.
As usual for questions like this, reading the linked Qs and having a firm grasp of the historical pros and cons is table stakes for your answer to be taken seriously - please do your research before giving your opinion.
Note that CW can be used on questions (in which case all answers are also CW) or just on an individual answer. Its net effect on its subject is to remove rep and lower the already pretty low bar for editing it.