I really, really suspect that the big Lemmy instances are being run by Reddit admins or spooks or some-such. They’re moderating their instances in the exact same way Reddit did minus the profiteering. The censorship is the exact same.
It’s just the reality of online content moderation. The good mods/admins are people who are passionate about a topic and want to provide a space for discussion and community building. When it comes to the “power mods” or whatever, like those we saw on reddit who moderated 100+ subs, they’re just in it to stroke their own egos.