That's not what I would call a "normal" discussion on HN, but it does happen from time to time. A seemingly normal user that has interacted fairly normally for a while (enough to get a fair number of points) gets set off by something here, or has something else going on, or some combination thereof, and goes completely against the norms here.
The user in question made ~16 replies, 4 of them top level, and the majority of them (including some top level ones) one word or one sentence (and generally disparaging). When someone that has enough points here to indicate they've assimilated at least somewhat posts "lol" and "there is no spoon" as top level comments in addition to other ones and other disrespectful comments, my guess is there's something else going on and this is just an outlet for it. In that respect, I don't think it's indicative of HN, as I think it could have happened anywhere.
HN comments are a statistical distribution. If you make generalizations based on the long tail in the direction you dislike, you won't end up with an accurate picture or feel very good. Everybody does it, though, because we are primed to notice most what we dislike: https://hn.algolia.com/?dateRange=all&page=0&prefix=true&sor.... This seems to be an invariant of how human hard-wiring meets the internet.
This is a little tangential (and I'm NOT trying to claim the author is a bot) but wouldn't the first thing you'd do as a bot being called out as non-human be to proclaim "how dare you call me a bot!"?
The author wishes us to know they're happier about compliments on MR than the user on HN who obsessed about the article being written by a bot to the point of derangement (and perhaps more hurtfully, someone else who said "I don't think so" then edited the comment after reading more articles to say they'd changed their mind, but probably there was a human in the loop somewhere!)
GPT-3 wouldn't come up with the perfect clickbait title to post about being offended, so probably human :)
I'm not seeing any top comments talking about GPT-3 or anything that he talks about