Yeah, this is one of the most censored place around. It says a lot about the VC culture.
Presumably the assumption is that some good people will be banned and leave, and some other good people will just leave out of sympathy, but it's better to have good people leave than have bad people enter the community. It's an interesting hypothesis, and HN has been going strong for 5+ years now with minimal moderation effort, though I have to admit that it seems to violate basic rules of fairness and empathy. Then again, a lot of businesses are built on being unfair to people.