I don't think it's even about being moderated, but rather that in a small community extreme ideas won't find enough support to survive, if the community is reas

I don't think it's even about being moderated, but rather that in a small community extreme ideas won't find enough support to survive, if the community is reasonable. On the other hand, it's possible for extreme communities to emerge too, but I would say that this type of fracturing is more like real life groups than not.