It's not the censorship itself (which is also dumb, but it's a different kind of thing), but rather the way the censorship is run. Like, Weibo definitely seems way, way more OK with people flinging shit at each other (just not at the government, but fandom in-fighting is not really worth their time to censor). Meanwhile, it seems like Lofter wouldn't even allow mildly caustic language, which is a bit prudish and puritanical. (Of course, doesn't stop people from posting art and fanfic on there somehow, I don't really know how those people managed to get around the censors.)