They don't understand that to most people outside their queer social circles, TWAW/TMAM is just a polite fiction. Some exceptionally well-passing trans people might be accepted as effectively real men/women in most contexts, but that's on a case-by-case basis and much different from what TRAs are pushing (i.e. that any obvious male who says so is literally just as much a woman as your own mother), and even then it only goes so far.