In the last 30 minutes they fixed the misspelling but kept the text as it is. This means someone is currently following this problem and thinks they are in the right by doing this.
Unless this hacker was able to get the COO's HN account as well that seems unlikely. And even then a call to someone at YC to jump into the thread and let everyone know it was a hack wouldn't be too hard.
But by linking mental illness to scumbag behaviour you're making life worse for all the people with mental illness who aren't scumbags - which is most of them.
A group that I am a member of. Perhaps I'm biased but I don't feel like my life is particularly worsened.
I've had the misfortune of bearing witness to paranoia fueled by both mental illness and drug abuse (and a combination of both). I've also worked with and for unapologetic assholes. There are things about this case and his communications that have me leaning toward the former.