"I didn’t say anything about labeling people based on their brain structure."

Yes, you did: you said that men and women have different brain structures, implying that if one has a brain structure that is common to females, then one is "really a female".

I politely reject that. I claim that to do that is to label someone according to their mind and how they think.

"therapeutic analysis to confirm their experience of gender"

That is even more subjective: labeling oneself based on "how one feels". Why do that? Why put a label on yourself?

I claim that such labels are useless. In face, the label of "male/female" is pretty useless, EXCEPT that people often like to know, because most people (not all) want to have a family, and so they need to know the sex of the other person - and that is really the ONLY reason.