If my friend asks me what sex Robert identifies as, I'm going to say that he identifies as male. Would I be lying? I'm not calling into question the fact that you are a man, nor am I saying that you "only think" you're a man. I'm just saying that, for whatever reason, you identify as a male. You seem to think the word denigrates your certainty; it doesn't.

I would never say that a girl who prefers cars is transgender any more than I would say that a homosexual is transgender. But that does not rule out one's sense of sex coming from behavior. You say you're a man because of your plumbing. Trans women say they are women despite their plumbing. Are they just wrong? As I said, one way of resolving this issue for gender critical thinkers is to declare trans people delusional. And, if they are not wrong, what is their source of information concerning their sex?