Sure, !kde@lemmy.kde.social for example

I honestly wish more devs did this. I can't stand discord and their "kitchen sink" philosophy and the fact that content on discord isn't indexed.

I suggest looking into NodeBB, I think they are optimizing for this kind of use case.

The only downside would be occasional inter-instance drama and the need to update the federation blocklist occasionally. This could be avoided by using an allowlist (instead of a blocklist) and only federating with a handful of well-run instances.

At this point if you only federated with lemmy.world and no other instances you'd be getting 90% of the benefits of federation and 10% of the problems.

If it's going to be federated then it will be more like a subreddit than a separate forum. If it's not federated I don't see the point of using something like Lemmy for a few communities compared to something like Discourse, which is more polished and battle-tested

I get it that dealing with yet another account is annoying, but how will you cope with the bots and AI spam?