“But the premise of this reasoning rested on the idea that men and women are inherently, innately, mentally different.”
This is my response:
No, it’s not. It’s based on the realization that gender is complex and is made up of a variety of separate aspects: 1) genitals, 2) gender identity, 3) gender expression, 4) chromosomes, 5) secondary sex characteristics, 6) role in reproduction, 7) societal roles, etc.
To admit that gender identity is immutable and may not correspond to original gender assignment (which is usually based on genitalia) – is not throwing out the powerful idea that a great deal of baggage that is assigned by society to the binary essentialist “man and woman” is completely crap. To admit reality is not losing some sort of ideological fight for socio-economic gender equality or the fight to demolish patriarchal “dominant/subordinate” gender concepts.
PS: To be even clearer. A woman and a man are not “inherently, innately, mentally different” in any other aspect but their gender identity. In fact, they are not “inherently innately, [physically] different” either. Call me a “gender essentialist” if you feel like it, but that’s more defensible than being a body essentialist to the point of denying reality.