I don't go to HN or Reddit and get anxiety about all my friends posting about their awesome lives. I go for information only.

Forums, imageboards, and psuedonymous or anonymous places are not the same as Instagram, Facebook, TikTok, etc

>If Facebook decided to allow pseudonyms, would it not be social media?

You can name your account anything on Instragram or TikTok, but even so most people will connect it to their real identity, add all their IRL friends, etc. Not the case on HN Reddit or any other forum