[panopticchaos]

I'm on the fence about Lemmy/Kbin, but I think it has a better shot than Mastodon.

Twitter's thing was "giant conversation with everyone" - federation interferes with that.

Reddit was inherently fragmented (subreddits, and heavy redditors tended to describe groupings of related subreddits). Federation seems pretty natural here (community names can just have an @ symbol somewhere in there).

There are UI and discoverability issues, but those seem rather tractable.

I think performance at scale will be a real issue though.