My (rudimentary) understanding is that something is bio essentialist if it is wrongly attributed to biology/sex. So saying girls are innately less intelligent is bio essentialist because intelligence has nothing to do with one's sex. But saying girls have ovaries is NOT bio essentialist because females have ovaries by definition.

I do find it kinda ironic, for as much as QT complains about bio essentialism, they're the ones that usually put forth the female/male brain thing. That seems incredibly bio essentialist to me. Also the gender euphoria thing seems kinda bio essentialist, to say females should feel euphoric for performing feminine actions. As if we're somehow predisposed towards those actions.

If male and female is defined on the bases of sex organs and gametes, then why is a male still a male and not sexless or less of a male after removing all his sex organs? Why is a female still a female and not sexless or less of a female after removing all her sex organs?

A bicycle has two wheels, if we remove one does it become a unicycle? Of course not, we can still recognize it as a bicycle that is missing one wheel. Just because something isn't in its most textbook, typical, ideal form doesn't mean it isn't that thing. Not to get pretentious but there's the concept of a "platonic ideal", where we can imagine the ideal form of something. But those ideal forms never actually exist. For example, we can imagine an ideal apple in our imagination, perfectly red and round. Apples in real life might be less red, or kinda lopsided. No apple in real life can match the ideal apple in our heads, but we still recognize those apples.