The part that doesn't make sense to me is: Why? As in what are the incentives to use AI to write comments on HN? This is not a platform like Youtube or X where views get you money. Is this just for internet karma?

I think it's just people experimenting with conversational bots. If you can get your bot to participate in a conversation on HN without being identified as a bot then it's better than those that do.

Bots need content from somewhre, they either copy something else or use ai to generate.

The incentives to use bots are many.

People have posted their blogs here before and gotten the HN hug of death plus a few hundred comments. It's 2026 and not 2016; HN is a much larger platform than people seem to think it is and HN has significant eyes to be shifted if your posts reach the front page. And given how cheap it is to throw bots at whatever site has open registration it doesn't surprise me to see manipulation here.

I know on reddit since basically the very beginning there has been a market for accounts with authentic but anodyne histories. It ends up being easier to make them yourself and then just occasionally use them for whatever guerilla marketing, astroturf campaign, or propaganda operation is your actual goal. But still until recently you pretty much had to pay people to sit and post on social media on a bunch of accounts to generate these histories.

This use was one of the first things that occurred to me when LLMs started getting genuinely good at summarizing texts and conversations. And I assume a fair bit of this has always happened on HN too. I've never moderated here obviously so I have no first hand insight but the social conventions here are uniquely ripe for it and it has a disproportionate influence on society through the dominance of the tech industry, making it a good target.

Getting stories on the front page of HN can get them spread across the entire media. Also, you end up with a bunch of accounts that can upvote comments/posts that you're pushing and downvote/flag the ones that criticize them.

Lots of dumb blogs from unknowns about vibecoding entire products in a weekend using specific AI slop generators from new startups that are getting to the front page lately.

remember: 1) those accounts that are causing 10x as many em-dashes are the dumb AI accounts. The smart ones are at the least filtering obvious tells from the output. They might even outnumber the dumb ones.

2) Also, a lot of people are real, but using AI to make themselves sound smarter. It's not necessarily completely nefarious.

Using em-dashes as an estimate has to result in a bunch of undercounting and overcounting.