I think there are good reasons to not let corporate interests join the space we built to escape them, but I guess every instance is free to (de)federate with whomever they want.
So let’s say my instance (mander.xyz) defederates from Meta but another Lemmy instance that meander.xyz federates with (let’s say “misguided.ml”) does not. What happens when someone from Meta comments on a post from misguided.ml and others from misguided.ml comment on that comment? Will I see the comments on the meta comment, but not the original meta comment itself? Or will I not see the entire thread?
This is what could happen. Learn from XMPP and don’t let corpos into the Fediverse.
ActivityPup is an open and public protocol. Anyone can use it however they want, but as a community we do have some control over who we federate with, so excersize that control.