My point is there are affectations in both communities (4chan and HN) that are strange opposites of one another. Here, people often pretend to be more polite and erudite than they are, there, people often act more rudely than they normally would, because that's the culture, that's the mask you're expected to wear.

And on both sides there's a pretension which you're kind of displaying. You're talking about a site as vast and varied as Reddit as a whole as if it were a single forum, and dismissing it as qualitatively lesser than an anonymous imageboard that has shitposting as a central part of its identity. Find some well moderated subreddits for any particular genre and you'll find quality of conversation equal to anything on 4chan, or even HN.

Also, you know, 4chan has been around long enough at this point that a lot of "out of touch academics" and "journalist boomers" have probably been there.