Trans women on HRT experience hot flashes, breast development, fat redistribution, and muscle atrophy that cis men simply don't.
We're physically closer to cis women than our former selves. If you actually cared about "biological reality," you'd acknowledge hormones drive these characteristics, not chromosomes.
You don't check anyone's karyotype before treating them as their observed sex.
Treat trans women as women (because we are) and stop being an asshole.