How many SEXES are there ? Is the correct question
Two sexes, just like there always have been, and always will be.
Genders? Also two. Their usage depends on which of the two sexes is associated with them in the writing.
Yes! Two sexes and however many genders you chose to imagine. It is a huge mistake to argue there are only two genders — that only clouds the issue. If you’re discussing public bath/change/dressing rooms — the issue is sex. For instance, an intact male is capable of raping a female — regardless of which gender he has identifies with, in his delusions.