Yeah for sports idk what to do, none of the solutions I think of seem to fit. Sports are designed to be unfair it's a competition after all. And apparently in women's sports accusing competitors you dislike of being a man is just a thing we do (if not the athletes themselves then the general public). Biology is weird and biology of Olympic level athletes is going to be even more weird and deviant.

As for definitions, the competing definition being argued for in the article is self id, with several anecdotes detailing why this is a better idea than gamete size or chromosomes or whatever.