"Gender refers to the psychological, behavioral,"

But how do we know that psychology, which is generally based on correlative studies that don't pin down cause-and-effect - is not being influenced by our culture, which is currently advancing a narrative that gender and sex are distinct? What about biologists who dissent from that, and are censured as a result? (There are quite a few examles of that.)

"your assertion that there are no meaningful differences between 'male' and 'female' brain structure or function"

No Sadie, you misunderstood my meaning. I agree that there are aspects of the brain that are _correlated_ with males and females. But just because someone's brain has many correlations with female brains does not mean that we should _label_ that person as "female". After all, a gender is just a label. Do we want to _label_ people based on what is in their head?

Perhaps next we should start labeling people based on whether they are introvert or extrovert - call the introverts "I" people and the extroverts "E" people, and create a separate pronoun for them.

Reproductive biology has led to the male and female label because of the very important issue of who one can raise a family with. That's the only reason why it matters - no other.

I don't agree that we should be labeling people based on whether their brain leans one way or the other. I thought that we were getting past categorizing people: finally women were allowed to do all the things that men do. Now the trans community is taking us back to labeling people.

Aside from one's reproductive sex, any concept of gender does not matter - should not matter.