Most women I know don't post about their problems on social media, and it's likely a combination of demographic and risk, that and high availability of counseling and therapy. This is without even getting into a lot of men I know posting about it, including me. It probably skews about even.
In 2024, there's been an exodus of certain demographics from social media. Does his research take that into consideration? It's just a stupid and sexist comment on HN that deserved to be called out for being a stupid and sexist comment, nothing more.
Even you yourself say it ‘probably skews about even’, you too have no evidence.
No need to accuse the commenter of sexism. It can also be an innocuous observation of their social media feed.
Absence of proof is not proof of absence.