But if you want to play the "intuitive, common sense" game, here's a trans man:

To 99.9% of us, we would see this guy and immediately assume that he's a man. And that's because he is. He also could probably get pregnant. Guitarguy would go against all reason and logic by calling this person a woman. That makes no sense - if any of us interacted with this person, none of us would ever treat them in society as a woman or use she/her pronouns because that would be ******* ridiculous.
Obviously, genitalia isn't the signifier of gender, because otherwise, you would have to take the ridiculous argument that men are women and women are men. No one actually believes that.