Wow, I realize I really need to update Navigating Fedora Discussion — Tags, Categories, and Concepts 
For Project Discussion, all tags should represent specific teams (with the current broad exceptions of engineering and mindshare). And, I don’t want them to be ghost towns — we should only create them for active teams.
For Ask Fedora, anyone with TL3[1] can create tags. We could consider lowering that, but it’s already a little more of a mess than I like. But, also here, tags shouldn’t exist in a vacuum — and in fact tags which aren’t used on any posts are automatically deleted after a short time.
So, rather than abstract, the answer here is to find posts which should have these tags and add them. I happen to know (because we just discussed it) that you’re right on the verge of hitting TL3, so I think in this case the easiest thing is to let you know that you are (soon) empowered to just add them.
However, if you want to go on a wider campaign of tagging dozens or hundreds of posts, we should probably coordinate. There are ways to do that without causing each one to get bumped and notifications sent.