I recently proposed (Do we need tags for highly specific elementary mathematical topics?) we cut down on the number of tags on highly specific mathematical topics.
However, I've thought for some time that there's a significant number of issues with the tags we have. Rather than creating a post for each one individually, I figured it might be better to have a single post to collect these, and more handly collect opinions about each proposal.
I'll start by adding the ones I'm aware of, and that I most often found frustrating to deal with when deciding which tags should be used in a certain question (and as you can see, there's already quite a few of these). Please feel free to add other answers about any other issue (related to tags) that you think needs fixing. And remember to upvote/downvote on each proposal you agree/disagree on, and add comments to voice disagreement or suggestions to modify a proposal, or anything else.
I'm featuring this post to give it a bit more exposure, in the hope of enough people seeing it to create a meaningful volume of discussion, and maybe also capturing some other issues other people might have seen and tag-related proposals they might have.
After this is done, I also think it will be a good idea to have a general discussion on tag management, to avoid having to do this again in the future. I'm thinking another meta post where we decide on general guidelines of which tags we should and shouldn't allow. More specifically, I think it's a good idea to have guidelines of the form "users should be allowed to create tags of type X and Y as usual, whereas tags of type Z and W should require a tailored meta discussion beforehand", where X and Y might include for example "tags about specific quantum algorithms" and Z and W might include for example "tags about specific classical programming languages". Anyway, that's for later.
EDIT 14/10/2023 — I think this has been up for a sufficiently long time, so I'll start rolling out the upvoted proposed changes.