When Bruce Jenner dies there will be a man's skeleton in the coffin that people will be referring to as "she" or "her".

Conversely race is a social construct for obvious reasons, for example where on the map is the country of white or black?

Therefore neither of these concepts-- be it race or transgender are real. They are imaginary constructs people choose to cling to in order to feel and or exercise power in some way shape or form