Private restrooms for each individual is a solution that makes everyone happy but large public restrooms are that way because of the number of people involved. No one wants to share the facility, it is just a necessity (or at least it simplifies things greatly) to deal with the number of people coming in and out.
I am confused how making a trans gendered person (who has made a very difficult and very defined decision regarding what sex they want to live their life as) identify themselves as male or female before going to the bathroom victimizes them.
If those individuals are being stopped and questioned, made uncomfortable, singled out, or made to feel like less in any way then THAT is the part that needs to be changed. But someone who has made the decision and taken steps to live their life as a male despite the physiology they were born with has decided a lot more definitively than I ever have that they are male long before entering a bathroom.
for what it’s worth, my comment above regarding naked people having more sex was intended to lighten the mood a bit, sorry if it was misunderstood