There are at least 30 genes scattered through DNA whose interaction determine sex/gender/sexuality characteristics. It was once thought sex could be ‘eyeballed’, and later thought X vs Y could determine. In the first 2 decades, we learned it’s nowhere near that easy.

You can’t reliably determine within a P value (sorry, your made up fraction of a percent number is scientfically inaccurate) without a full genetic assay.

What the doctor writes down as ‘sex' at birth is nearly always, at best, just a very rough guess that’s gets assigned to the person based on that guess. This is the current scientific consensus. You can continue to be bigoted towards trans people, or you can be right; but you can’t be both.