Up to 1.7% of the population has intersex traits, comparable with the proportion of the population that has red hair.
No one would be so foolish as to deny the existence of red-haired individuals. The only difference is you can see red hair, while people’s sex traits tend to be private. For good reason.
But of course, now we live in a world where some Republicans want to do “genital inspections” on children. They’re the ones invading privacy, not trans rights proponents.