It's not just getting the facts wrong, it's often about them misunderstanding the topic entirely because they didn't bother to read.
I don't think it's about being human, I think it's because HN is a BBS where people can get points by chatting, which also happens to link to articles which you can read if you feel like it. Of course this is how it ends up.
People play the game according to the rules they're given. In the early days when HN was more caustic, you got more points by reading the articles and posting accurate facts. But in the dang era where comments are required to be nice and calling people out is discouraged, you get more points by rushing to post something plausible-sounding and vaguely related to the headline. So people do that instead, unsurprisingly.
Indeed, the rules are slanted to give bad-faith word-salad as much of an advantage as possible. Even the site's layout is hostile to correcting those posts; in addition to the rules prohibiting us pointing out that the article doesn't say what they claim (because we cannot directly imply that they did not read), the formatting of quoted text is messed up and ugly and distracting.
On this current account, I don't really care about overall karma, just per-post karma. I try to post simple but defensible points when I get early top-level timing, and I put effort into upvoting people that I agree with rather than adding on yeah-me-too posts for more karma. But I'm punished for not playing by the rules of the game; I can't downvote or vouch or any other useful features, so (-1, flagged) is a common fate.
In the design circles that I frequent, we often consider Conway's Law for social communities. The API of HN, including the rules, generates the shape of the conversations. The shittiness of discourse here is inherently due to the low-quality rules just as much as the lack of meta-moderation.
I don't think it's about being human, I think it's because HN is a BBS where people can get points by chatting, which also happens to link to articles which you can read if you feel like it. Of course this is how it ends up.