Transgender Sports- A Tough Question

[BFritz21]

If we keep going down this slippery slope where it's ok for a man to change with women or even girls because he identifies as one, and say that a man is a woman if he feels like one, regardless of his physical sex, then do we let a man play a sport with women or a boy with girls because that's what they identify themselves as?

Say that there's a basketball tournament with the championship team getting millions of dollars and merchandise deals, would it be ok for five NBA players to just say that they suddenly identify as women, go in, blow out every team in the tourney, and win the money that should belong to the natural women? Even if the NBA players weren't pretending, would it still be ok?

My original thoughts were because of the Olympics, but I'm thinking that the Olympics wouldn't even be a question that they'd make them be with their natural sex.

If we say that a man identifying as a woman is a woman, then isn't it impossible to draw a line anywhere?