A quick thought. So, natal males can only compete if they are controlling their testosterone levels down to some minimal number. OK, so that’s doping and it’s allowed because the absence of that testosterone reduces performance.
Going the other way, boosting testosterone, is very naughty and banned and gets you thrown out.
Which is proof of why we have the different classes, male and female, as the testosterone level matters, no?
The very acceptance of doping to get testosterone down is proof of the contention that male and female, biologically, are different.