Firstly, it's good that you're willing to change your stance on an issue when new evidence emerges to suggest that what you previously believed was right was wrong.

One thing that I think needs to be drummed into some people who oppose transwomen in women's sports is this. And I'll use an analogy from my native Australia. A 20-year-old wants to enter politics, so they joined a political party at 19, were preselected at 20, but failed to win a seat, and the branch president takes them aside and says, "Don't be disheartened. Finish your studies, or work for a few years, and if you want to, try again." And they decide after nine years to stand again and this time, they win a seat. No coach is going to take an 18-year-old cisgender male athlete aside and say, "Look, I don't think you've got what it takes to be a male competitor, so get a testosterone blocker and some estrogen from your doctor and try again in a couple of years but this time in the women's group." That would be a recipe for disaster.

I concede that many of the transwomen want to play sports that were traditionally male sports, but the reason for that could be more nuanced than people are prepared to accept. Namely that although a person is not cisgender, they may have been forced or encouraged by their parents to play football, for example, and they had a real talent for it, and despite wanting to transition, they still wanted to play football. I think their eligibility should be decided according to their hormone levels.

One thing that also needs to be borne in mind is that some athletes will always have a natural advantage. For example, Michael Phelps with his large feet.