As anecdotal proof, I recently got upvoted 13 points for saying "I thought some of his suggestions were pretty decent. But then he just threw everything away by mucking around in the Code, I mean Overview tab. His last design, without the guiding lines, make it look like jumbled shit pie."
Not only had this same thing been said multiple times already, but I said it less well and was vulgar. I wouldn't have upvoted me Its not that I disagree with what I said, but I could have made more thoughtful. I could have done a point by point critique, showing what I thought he did right and why, and what he did wrong and why. But I didn't. I was lazy, and I said it in a way that got upvotes.
On the other hand I've spent time, up to an hour, writing careful precise comments and gotten not a single upvote, maybe some downvotes.
So, in my view, HN has a feedback mechanism that rewards trite, thoughtless, vulgar commentary. And as folks here ought to know, if you want to increase the frequency of a behavior, you reward it, and if you want to decrease the frequency of a behavior you fail to reward it.
To close, I will say one thing that HN has in its favor: trolls, goons, and jerks tend to get shut down quickly, and that's great.