Individual instances will have to moderate themselves. If they become chaotic, other instances should unfederate them. But as users, you should also subscribe to communities you think are behaving well and block users/communities that are not.

Also, I have seen some users who are "grabbing" as many communities as possible, namely @[email protected]. Dude is moderating 60 communities, in an instance that started a few days ago.. He is not building the communities, he is just power tripping it seems. @ruud@[email protected], something might have to be done about that in the future. I suggest some sort of "requestcommunity", in which you can apply to become the mod of said community, if community is being badly run (or not run at all).

I'm wondering the same, I would guess grey listing and shadow banning to be the most effective.

Their own way. If they don't control their shit, they get defederated. Such is the way. Keep your nose clean and you'll be right as rain.

But I do wonder about the possibility of two Lemmy communities, one right-wing and one left, with the right created in protest of being defederated...

Well, we can't think about that all the time, can we?