I understand that they are staunchly pro-communist and also take a pro-Palestine, including some of them (many of them?) a more clearly pro-Hamas stance. And that all of this could annoy many of the centrist liberals that seem to dominate here. But from perusing the lemmygrad link I do not see clear signs of hate speech, certainly not a clear hate speech agenda as you would see with some hate groups. And judging by the comments on here many seem to be happy to be “rid of them” because they are “annoying”, or “immature”, or “tankies”, or whatever. It really reads largely like “their opinions annoy me” so I’m glad they’re gone.
There may be more to it, I don’t know, but personally I wouldn’t like lemmy.world, an otherwise fine instance by all means, to become a centrist liberal silo where no other opinion outside (mostly US-centric) liberal orthodoxy is heard. So yeah, not convinced that this was the right decision, basically because of a lack of evidence.