what does hellbanned look like on HN? Can't login? Can't post? Can post, but noone can see it?
Though it happens less than in other forums, wagon circling is definitely a persistent problem on HN. I believe it's only further exacerbated by the fact that downvoted comments are displayed in a difficult to read color, meaning that downvotes can effectively censor things the majority doesn't like, regardless of the merit of the argument. It's not as bad as on Reddit, where groups of people form downvote cabals to actively censor specific users or ideas, but it's still problematic.
In general, a 1-line downvoted post is downvoted for good reason. For multiline posts, it's far more often a good post that people didn't like for other reasons. Those are the ones I take steps to manually highlight and read, and then upvote if I think it was downvoted for the wrong reasons.
If you have showdead on, sometimes you'll see perfectly reasonable comments that are inexplicably dead-- this is why.