Such is the reason HN thrives. Though experience has led me to reason that such behaviour is applied to anyone who sets out to tarnish someone else's reputation. Not only YC people/startups.
>I've even seen high karma members get completely banned because of submissions about Curebit and AirBnB.
Karma is not a good indicator of anything. One can easily gather "karma" by writing useless blog posts that rhyme with the general schools of thought (or thought patterns). I think karma is used here as a tool to promote valuable links that add to the conversation, rather than a tool that measures social hierarchy. Karma does not measure a poster, but the post itself. If you post anything that violates the rules (which are sensible and permissive), then you have proved, without a doubt, that you original intentions were not inline with the "belief" behind HN (information that are interesting to hackers (though inflamatory posts are not interesting)).
>When you come to one persons house, you can't argue if some ground rules are set.
We are also born with gravity wrecking havoc around the universe. What good does bad-mouthing gravity do? =)