I'd much rather "performative erudition" than "performative idiocy" (a.k.a. trolling), because the latter makes visiting idiots feel they're in good company[0].
Funny in its way. I was thinking about this a while back. IMO HN as a community is mostly introverted (subjective/qualitative) and structure-biased, so open-ended discussions on "erudite" topics which may not be direct specialties of commenters will encourage a sort of performing or even bluffing effect, out of community-identity stress.
At that time I think I concluded that the least-pressured conversations, and likely most positive and upbeat, would be those on topics like retro computing. Such a topic is close to the HN tech-user specialty, close to the heart because of its strong integration with personal past experiences, and mostly made up of "known" or "closed-ended" topics. So, far from a performance or bluff, you get some pretty passionate tales from direct experience, and erudition be damned.
Not sure if that's a rule, but so far it matches my personal perceptions of what makes a really good discussion here, vs. one that's...less like that.
[0] Paraphrased (surprisingly to me) from a Hacker News user: https://news.ycombinator.com/item?id=1012082