I guess I have a different perspective on HN than you do; because I've never noticed the "cool kids" wasting their time by griping about stupid questions (presumably they just scroll past them), and I've never seen anyone I consider one of the "cool kids" give warning that they were going to leave HN because of stupid questions.
EDITED to add: And I do know smart, successful, insightful people who don't post on HN precisely because of the kind of behaviors that you want to "let slide".