In my opinion there are physical and psychological genders. Physical being genitalia, and if you go by that alone there is 4 as you can be born with both or none. Psychological being what that person feels they are.
This whole gender debate and what bathroom to use is kinda silly. It doesn't take much to design a single sex bathroom that accommodates everyone. Been in a few, each stall was separate, with door the close off each stall, you walked in picked any stall did your business walked out to the sink area, and washed up. Yes there were urinals, in a small stand up stalls and clearly marked are urinals. Easy yea the first time I was in there it was a little bit of a shock to see women in there too, but nobody ever saw anything and once you used it once or twice you did't think anything about it.
The very point of gender is that it is socially constructed. It's a social agreement, not a biological fact. (Yes, gender is related to an underlying biological fact; no, that is not remotely relevant).
In a state of nature, no one is an accountant either, and yet we have regulations and recognition of that job.
Societies are supposed to accommodate, within reason, the people that live within them. Abstract principles are never particularly useful as guides in that situation: you figure it out on a case-by-case basis.
Accommodating people who view themselves as another gender is easy. It is not a particularly difficult challenge. Do you have to memorize the seventy or what not genders that folks have created? No. When someone asks you to accommodate their specific gender identity, is it reasonable to deny them? No. It's a simple matter of courtesy.
The science is pretty clear: gender dysmorphia is real, it has biological antecedents, and it is not an illness. People who identify as transgender should receive support to deal with the secondary symptoms that may stem from gender dysmorphia, but the underlying condition itself is not a disability or an illness. And even if it were, leprosy is undoubtedly an illness and people accommodated lepers in the past too with appropriate changes to the social contract.
There's simply no justification for choosing a priori to make some portion of the population uncomfortable. No one would want that done to them, so it is a moral grotesquerie to do it to others.
There are chromosomes defining your gender inside EACH fcking cell of your bodie. Stop being retarded and say i'm not feeling like a women/men so i'm not. you are just a men or a women that can't accept it. We can't do nothing about it but if it pleases you to lie to yourself go ahead.