Isn't that mostly a result of how much you want to focus on the outliers? XX male syndrome is estimated to exists in 1:20000 - 1:30000 people. It's so rare that we have a name for it. Somewhat like rebutting to what a car is by arguing that a handful of cars through history actually had two wheels. And yes, I'm aware that XX syndrome isn't the only outlier but the point still stands.
If there are outliers you don't get to change the definition of the established binary and force the outliers into them. The outliers are just that, outliers, a 3rd, 4th, etc option.
If you argument is that there are more than 2 genders, that's fine, Man, Woman and whatever else.
They are outliers that have their own names.
Certain things are constant though
Man: Adult Human with XY sex Chromosomes
Woman: Adult Human with XX sex Chromosomes
Everything else and I mean no disrespect with this term, are mutations that fall outside of the norm.
Surgery and hormones though do not change your sex chromosomes. You are still sex you were born as. You can be a trans woman, but sex wise you are still a man and vice versa for trans men.
I wish trans people all the happiness in the world but if you paint stripes on a horse its still a horse, not a zebra.
Eventually you'll realise that all labels have exceptions. Unless you come to terms with that, every definition will just be diluted to the extend that it loses all meaning.
OK so the definition is that a human has 2 arms. What happens when they don't have two arms? Are they a new thing? Or are they still a human that we should treat with the same respect we grant to everyone?
They are still human, just missing (or have extra) arms. We should treat them with the same respect and dignity as anyone else that have 2 arms. What we don't say is we don't know how many arms humans have just because some people have more or less than 2.
