I just remember it being a thing a while back between World, Hexbear, ML, ExplodingHeads, etc where admins had a clash of views and decided to just sever federation. Like I get that some instances are run be wackos and some people don't want to see certain certain content, but I'd rather make that choice myself as a user and block what I don't want to see, as opposed to my instance admin making that decision for everyone. One thing I always appreciated about EE was that they defederated from spam and unsavory (ie CP) instances, but they left the majority of it to the user. I'm just not a fan of blanket bans, even if I agree with it.