That idea works in theory, but in practice it makes comments a popularity contest. Eventually, people with minority opinions figure out that their ideas are unpopular and leave or stop commenting. The end result is monoculture. A great illustration of this phenomenon is Reddit's politics subreddit. In theory, it is a place to discuss American politics. In practice, its discussion is almost entirely centered around a single candidate from one party. The downvote button windowed the community and then winnowed it again until a political atom remained.

I don't think HN is monocultural, at least to a pathological extent. There's quite a bit of debate here. The overwhelming majority of grayed out comments are baseless, off-topic, or unnecessarily inflammatory, from my perspective. I think that's because there's a norm to agree with an upvote, disagree with a non-vote, and reserve downvotes for unproductive commentary. People seem to upvote unfairly gray comments regardless of their personal agreement.

I don't think it is either, but if we began downvoting for mere disagreement as the person that I responded to advocated, then I think it would.

>if we began downvoting for mere disagreement as the person that I responded to advocated

Downvote for disagreement has been on HN for longer than you've had your account.

https://news.ycombinator.com/item?id=117171

https://news.ycombinator.com/item?id=658683

Well, politics is a popularity contest.

If you actually wanted a discussion of political philosophy or to discuss other less popular candidates, there's other places for that.

Pretty much any subreddit reaches this state with sufficient time.

If that was the case, then this would be accomplished constructively by people upvoting a strong argument rather than downvoting an argument they have a disagreement with but either a lack of will or ability to articulate the reason they disagree.