That's why I like YCombinator, and consequently why I like Hacker News: it avoids that level of immaturity. All the HN users who have YCombinator-funded companies tend to have great conversations. I can't think of a troll here who also was part of YC.
That said, this is the exception. I can't think of many more online groups that are this adult.
My experience being a part of Y Combinator is that everyone is precisely the opposite, though my experience is limited them the people I've met directly a indirectly because of Y Combinator.