I’m subscribed to four communities named "fediverse@"something. Yes, it’s a bit annoying. But it’s also good to have backups, in the sense that I never know which instance might defederate from my own or from others who also use these communities.
Not sure what the point of this post is. Do you want people to vote on which to keep, and which to discard? They already do that. People subscribe and unsubscribe, post or don’t, as they please. Apparently, we continuously vote on having four (probably even more) redundant communities.