There are some on mastodon that want to live in a fairly defensively disconnected/defederated bubble (compared to many other instances or lemmy/kbin).

And, IMO, that’s totally fine and good … freedom of association gives people and instances that power and it should be embraced when people chose to exercise it TBH, so long as it’s done by admins in a way that isn’t too autocratic against their users and open and transparent.