To completely sidestep gender identity laws, why not have bathroom facilities based upon dick or no dick?
Have a dick? You must use this room to piss or change.
Do not have a dick? You must use this room to piss or change.
100% just boil it down to cock or no cock. I expect having it based upon anatomical reality of one specific organ can't be construed as denying gender identity. It's just cut and dry anatomy standards.
That is why I think making the dick the deciding factor will be the most clutch method of dealing with this AND sidestepping gender identity protection laws. I mean, damn, call it a feminine penis all you want but if you want to whip it out to piss you're gonna do it in the penis room.