I also agree with unisex toilets, since I'm not really sure what anyone would want to do in there that involves anyone else.
But the issue here seems to be that this man undressed.
Now I appreciate that the laws in the US often tend to be literal to the point of silliness, but here in the UK, someone undressing in any place at all for any provocative reason would be guilty of sexual misconduct.
A male, for example, can stand infront of a urinal and use it appropriately. But failing to re-dress himself even with the confines of the enclosed area could be seen as indecent exposure.
That could land him a prison sentence and an almost automatic listing on the sex offender's register.
To take the matter one step further. A woman who breast feeds her baby in any public place would be protected, if not by law, but by the public.
A woman who flashes her breasts in public for provocative reasons, would be guilty of an offence.
Just making those points.