It seems more common these days to use it on HN to express disagreement. That wasn't the case years ago.

I suspect it has to do with the reddit / youtube generation becoming adults. Polite disagreement seems to be on the way out.

That theory makes sense, though it's unfortunate, IMHO. Personally, I'd prefer for comments to rank higher based on quality (irrespective of which way they lean) than hivemind inclinations. Seek well-roundedness and all that.

If I suspect something is flamebait (ie, responses are not discussion I think belongs on HN as it's redundant/religious/reactive) and the content's value doesn't exceed that flamebait characteristic, I'll downvote.

ie, I downvote things that I feel have an aggregate S/N degradation multiplier.

I kinda miss /.'s moderation qualifiers.

With all due respect, as someone who has been participating in online communities since the days of FidoNet, I don't think people have really changed. There's just more people, which itself drives up the opportunity for disagreement.

And some of the most disagreeable people on my social media are old farts, too :)

Polite disagreement will often result in downvotes for oneself though. I think this is the problem?

Everyone votes by their own rules. There's no official guidelines on how to use the voting buttons.

Your comment inspired me to submit https://news.ycombinator.com/item?id=25636267