Hmm, so federation seems to be working, at least I managed to post a comment from another instance, and mod the user. What they've posted hasn't made it back here yet.
Some context: I have a bot I run on !dailybunnies@lemmings.world I set all this up before the site was geoblocked, otherwise I would have put it elsewhere. As it happened, everything still worked so I didn't immediately notice the blocking. The bot (which runs on Google compute in Belgium) stopped working today at the same time as Connect.
I'm thinking now that something has been hardened at lemmings.world which means it's pretty much unusable for me.