Why should they ban dios? Honestly, what makes Metafilter a great site— I've been a member there for a decade— is that, unlike a lot of fora, it still allows dissenting and unpopular views. I may frequently disagree with what dios says, but it's usually worth reading anyway.

I think a lot of people equate "moderation" with "deleting and banning". If that's a moderator's main tool, though, that moderator has already failed, IMO.

(Admittedly, Mefi culture has become more eager in recent years to simply quash posters or viewpoints that make them uncomfortable, which is a pity. I go there because I want find people intelligently and courteously expressing ideas I might not already be thinking. Lately Mefi has seemed less fruitful.)