Are you sure that they defederated, because from what I saw they just blocked some of the communities, it certainly was looking like it would end up going that route though, plus they were banning people from the instance in the thread who were speaking out or making points, it certainly was a feud between the two instances, but it didn’t seem like they defederated (though I do remember some very angry anti-piracy trolls calling for it).
I just want to say in case you didn’t see my other replies, that probably won’t work out as well as you think, because the way instance blocking works it only blocks the communities. User content still comes through.
From Join-Lemmy:
So regardless of the uninformed people suggesting this, it isn’t a solution to this issue, especially the hexbear spam problem, it’s not an alternative to defederation, and it never was, fact is Lemmy isn’t a free speech platform, people and instances can and will be banned and moderated, people who don’t like it just need to either deal with it or go elsewhere.