I don’t get the gender conversation. Before you discuss, define what gender means. After you defined it, it should be clear how many types there are or can exist.
If you can’t decide on one definition, then make up several. „Genders A“, „Genders B“, …
It should be very simple.
We could define two genders: Males are all humans larger than 175 cm Females are all that are 175cm or smaller.
Or we take the degree by what the jaw line is curved and sort it from most masculine with strong curves to most feminine with slow elegant curves.
We could go by genetics. Then we only have a handful of genders (xx, xy, xyy, xxy, … etc)
What I am saying is: define what it is first, and then the discussion is very simple. By my first definition there are exactly two genders, second one has infinite, third definition has a handful of genders.