Once again it's pretzel logic.
GC people have reacted to the suggestion that there are gender identities, and they are separate from sex, by saying "ok, it would be helpful to define gender identities so we know what differentiates a man and a woman under that system, but also let's keep things that are intended to relate to sex as that - relating to sex as separate from gender id".
It's the TRAs who keep insisting that their gender identity is their sex and needs to be treated as such.
I have rarely come across any TRA who wants to keep sex as sex and gender ID as gender ID. They are simultaneously separate and the same thing when it suits them.