Here (PDF) is some interesting — or depressing, or unsurprising, or all of the above — research on how people in online communities respond to feedback from their peers. The chief emphasis here is on how the more aggressive and hostile members of such communities respond to being called out for their bad behavior, especially when that calling-out takes the form of being modded down by other members.
Basically, the response of such folks is twofold. First, they make a point of downvoting other people. Second, they double down on their aggression. So: in online communities aggressive and hostile people respond to criticism by intensifying their aggression and hostility.
If such people primarily want attention from their peers, then the strategy is a reasonable one. Which is, in relation to my first sentence, why I choose “all of the above” to describe the research.
On a low-traffic site like this one, it’s feasible for all comments to be held for moderation by me. On high-traffic sites there seems to be no workable solution — except, of course, to eliminate comments altogether.