The "social purpose of the critiques is universal" is saying that, in opposition to the disparate and varied, personalized, nature of the specific critiques, their social purpose is all the same.
This universal purpose is saying "I felt uncomfortable ... might have to re-evaluate world view ... I'll upvote all the detractors".
> elevated personal impression of erudition
This is ironic, I have to say.
Anyhow, I found it easy to read the comment. It does flow a bit like stream of consciousness, but it's comprehensible, probably in part because I agree with a good amount of it. You shouldn't expect polished prose in comment forums on the interwebs.
If you felt that it talked down to you (personalized), then perhaps evaluate the social purpose of your own comment (did you feel uncomfortable? I got the impression you did).
As to your second to last comment, I wouldn't have even mentioned it had the other commenter not mentioned how they found the prose jarring. To your question in your final line, I didn't say that I felt I was being talked down to, I said that the author seemed like he thought he was talking down to an audience below him, such as with his line where he mentions his startup friends whom he shared his text with, but wouldn't share the same with HN.