It's quite possible meta stories are the most upvoted category of all. I posted an article about how HN was moderated and it netted more karma than anything else I've ever done on this site, by a wide margin.
Meta is the crack of internet forums, so mostly* a bad thing. We downweight it pretty proactively. There would be a lot more of it if we didn't.
Exactly, the "self analysis" bias is very strong and probably has its roots in psychology. HN's psychologically mature audience and mods (comparatively) probably tones down that tendency a bit, but many platforms need a separate meta category to prevent the community from spiraling around itself.