Who gives a damn where people poo? Why is this even remotely an issue? I am not even entirely sure why the hell we have "gendered" bathrooms at all from a strictly philosophical standpoint on egalitarianism. You know what I do when I go to the bathroom? I take a dump or a pee, I also try to avoid making eye-contact with anyone else in the damn place as does everyone else. This is a non-issue - for those of you who think this is a big deal... how the hell are they going to know? What, am I supposed to do, whip it out at the entrance to the mens' room? "Here you go inspector, I have a dong and identify as a male." Are they going to check my wife for a dick every time she goes to pee?
No, this sort of legislation is only in place to make trans folks feel unwelcome in society. It's not like these people "choose" to be trans - can you imagine how freaking terrible it would be to feel like a man but be a woman or vice versa? No one would voluntarily choose to make their life difficult that way.