Most of this comes down to the debate on the decisions of individuals. So if someone who used to be a woman becomes a man and wants to fight men then it seems like most, if not all, agree that that’s up to them. If they are at a disadvantage and want to take the risk then they can do it.
The other side of the argument is if someone who was a man transitions to a woman. Other woman in the sport have the ability to refuse to fight someone transgendered, but there will be consequences for it like losing a title. So basically they are forced to fight. It’s like if I hold a belt to my kids and whip them if they aren’t eating their food. Sure they can technically choose but in reality their choice is made for them.
It would seem that a study would need to be done of some sort to prove that a man that has transitioned into a woman has absolutely no unfair advantage over other women. This isn’t about racism or sexism. This is about safety and fairness. So if it is proven that there is no unfair advantage then I have absolutely no problem with it.