Going back for well more than a decade and a half I see people referring to DrDeth as “him” and never one retraction, so I think it’s safe to say that he identifies as male.
Also, I don’t recall him mentioning it once in this thread, where he tries to insist that any reference to the “Karen” trope is misogyny.
One thing DrDeth does often is fall prey to the “argument from authority” fallacy, and claims to be an expert in every little thing. I can’t fathom a scenario where he wouldn’t mention being a woman in that thread if that was the case.