Obviously so trans people can play sports, I think it's a laudable goal but I agree that people are going to great lengths to make sports 'fair' in ways that seem to only make them less fair to 99% of participants
Interestingly there were a couple of transgendered athletes competing in this year's Olympics: Hergie Bacyadan, a female boxer who identifies as a man, and Nikki Hiltz, a female runner who identifies as a non-binary. Both competed in their respective sports in the category congruent with their sex.
I guess your friend was aiming more towards not upsetting male athletes who identify as women and who desire to compete in the female category, by abolishing the category altogether, rather than these male athletes being told "no".
