This, along with the general hiding of points, reduces the amount of comparison to others that occurs on HN. That's different from conventional social media. There's still some comparison ("People on here know so much!"), but the impersonal aspect makes it reasonable to just shrug off.
Edit: Now that I think about it, HN is the only social media that I don't find it delivers enough value compared to my time spent on it (it does deliver value - it's just that it's a big time sink). I'm pretty happy with the time/value ratio of Facebook and (more recently) Twitter. It's probably because the ability to carefully curate what you see on FB and Twitter.