Self-Organizing Man

I’ve turned my brain into a pretzel contemplating this one, and it still doesn’t make any sense:

MTFs are supposedly 100% pure woman, never been anything else, and saying otherwise is "transphobic," but yet we get treated to photo features at the top of Alas with Nick Kiddle’s naked lactating breasts.

Did I miss the announcement that MTFs are women because they’ve undergone surgery to make their bodies passably female? Or is it some kind of zero-sum game where acceptance of MTFs negates acceptance of FTMs?

Someone out there must be able to tell me why the lactating breasts of a self-identified man contradict the idea that an MTF is a woman?