> XX instead of XY. The fact that 1 in a million people is neither a man or a women has no bearing on this fact.

Using the typical assignment of “sex” (really, a kind of gender ascribed based on a subset of sex traits at birth):

1 in 25,000 men is XX (approximately universally infertile, though chimerism might affect this, I guess)

1 in 15,000 women is XY (potentially fertile with HRT, and in at least one documented case, due to chimerism, without.)