I don’t see any obvious evidence of bot activity on that thread (and all of my spot checks strongly leaned human). Were some comments removed or something?

I noticed a few people on HN have started complaining that anyone arguing with them is a bot. I think it's a coping mechanism at finding people who challenge them, but maybe they've been on too many bot-infested forums lately, or are just young (that might overlap with both users of bot-infested forums and those who haven't had their ideas challenged much).