It is a size thing, but it's also a moderation thing. I haven't seen moderation this good anywhere else, no matter the size.

I think large scale makes it impossible to be good. Small scale doesn't guarantee good.

Reddit, slashdot, and a whole slew of others went through an HN-like phase of high-quality discussions and content before turning into cesspools.

I think what makes HN unique is benevolent sponsorship. There isn't pressure to grow. It's recruiting for Y-Combinator, which eliminates most of the normal pressures.

My favorite article on the life cycle (growth & collapse) of online communities is “Attacked from Within”* from the old kuro5hin site. I’ve always been curious to how it’s suggested solutions to the moderation problem would turn out.

* Archived here: http://atdt.freeshell.org/k5/story_2009_3_12_33338_3000.html

It wasn’t so long ago (less than 10 years, perhaps more than 5) that HN was full of similarly bad comments

i also think it's a content thing. the content of HN doesn't lend itself to lunatics most of the time. i say "most" because it certainly happens (see the early covid threads and the hatred spewed for anyone questioning or even just wondering aloud about the lockdowns)