And I'm explaining to you that gender identity has nothing to do with peeing. Biology does.
Self identity is a private matter. Public restrooms are, well, public.
If bathrooms were only about relieving oneself, biologically, there would be no reason to separate the sexes in the first place. A toilet works just as well for anyone, regardless of their sex.
It's sexual identity that determines the separation, not biology. Women want to be treated differently from men, and men want to be treated differently from women. This is not a biological desire. It's a desire based on self-identification. On how we think of ourselves, and on how we want others to think of us.
No one sees anyone else's genitals in a public bathroom to care what's actually between their legs. It's all about the
idea of gender separation, not actual gender separation. Which is why basing a law on actual gender separation doesn't work. It would force people who look act and feel like women to use a men's bathroom, and people who look and act and feel like men to use the woman's bathroom. Which is the exact opposite of the desired outcome.
Most transgender people are not detectable in public, or in a public bathroom. The few who might be are so small in number as to be insignificant. And no one knows what their sex is, anyway. So they could just be a very masculine looking woman or a very feminine looking man. And frankly, who really cares but a bigot, anyway?
This whole debate is once again about bigotry, and people wanting the right to discriminate and punish anyone they don't approve of. It has nothing at all to do with who is actually using which public restroom.