that's probably above the head of a typical user but yes, someone with technical expertise could also do that while still being able to access most of the network (and Beehaw) via federation
unfortunately that sort of granularity isn't possible with Lemmy, no--at least not yet. i would say we are open to the principle of giving different viewpoints their community if the activity is there, though. in the future, for example, we might give socialism it's own community because one socialist subreddit might eventually move here, and they'd be a decently sized contingent.
more or less, yeah-- there are benefits to letting people create their own communities, but with our size and intent we didn't think it really made sense and i think that choice has been successful, so we probably won't revisit it anytime soon. if it's a dealbreaker for some people, though, that's fine. we only block one instance so they can pretty easily use another one with community creation enabled, and they'll still be able to see and interact with the posts here easily