1. Continuing to swim as a man would induce dysphoria and affect her mental health.

2. In sports where testosterone levels matter, trans women are typically not competitive with cis men. There is a performance drop with transitioning, which is what I am pointing out.

To stay competitive she would have to wait on medical transition until her career was over (Caitlyn Jenner did this). Not all trans women can stand to do this. It's not fair to ask them to make that choice.

Think about how you would feel if somebody addressed you using female pronouns. Do you feel an incongruity there? Not everyone does, but most cis people don't react well to being misgendered either. It just doesn't happen to us as often.

It's a tricky situation to be fair to *everyone* involved.

Thomas isn't "choosing" this, she's trying to balance her career and her mental health. And has had the former taken away from her.

Which happens a lot to athletes who take the time to handle their mental health, just saying.