Yamato is a fangirl taken up to eleven, a stealth parody of the women who have totally believed similar things, and none of the insane people Oda is making fun of got the joke. (Actually, how many pooners have seen her as a spirit animal, now that I think about it?)
At the end of the day, Yamato's character development will be finding her real self-worth as a woman, and the trannies will seethe some more and pretend otherwise, especially if she ends up a mother. They're all still in denial over official databook and art that clearly tells everyone she's 100% female because they want to be an IRL anime girl.
Meanwhile I remember discussion about what Ivankov's true gender may be, and how literally everyone agreed it didn't really matter since Ivankov is Ivankov. It honestly would've been funny if he was biologically female, but it's a no duh moment he's just a loony guy just like Frank N. Furter he was based off of.