"Please don't post shallow dismissals, especially of other people's work. A good critical comment teaches us something." (https://news.ycombinator.com/newsguidelines.html)

That's a direct reference to pg's original concept of middlebrow dismissal. We just changed the word from 'middlebrow' to 'shallow' because the word 'middlebrow' often comes across as a putdown and also often comes across as labeling a person rather than a post.

Commenters who've actually read an article are always welcome to respond with accurate, interesting information from the article. That's a fine contribution. What's not fine is the "did you even read the article" internet trope.