"fairness in sports", bigotry
Here's your obligatory reminder that nobody actually cares about "fairness in sports", and any time someone raises that argument to try and exclude someone, it is going to be bigotry. There's no point in trying to earnestly discuss the topic with them, you'll just give them a platform.
If people *actually* cared about fairness in sports, competition brackets would not be divided by gender/race/whatever to begin with, and would instead be based strictly on real-world performance metrics. But you'll never find the "fairness in sports" people arguing for that.