Coming to this debate rather late, sorry.
For me this also highlights the danger of suggesting that choices don't have consequences - that you can have it all.
I am of the view that sex is a biological reality, and gender a social construct which layers assumptions and stereotypes onto biological sex, so perhaps see things through this lens.
I do have compassion for those who feel for whatever reason they are being asked to live under the 'wrong' gender assumptions, and understand that they may wish to 'change'. However with all choices come trade offs. If it is so desperately important to your own mental health, well being and sense of identify that you present as female having been born male, then by all means do so - how far you go in terms of hormone treatment and surgery should be your choice.
But in making that choice you may have to accept that some other things will be closed to you in future - one of these may be pro-sports. This is not because trans people are being punished, or because of an anti-trans view, but to be fair to the whole.
Everyone has to make these trade offs in life - women who compete at the top level in sport for example throughout their teens will have probably not enjoyed many of the typical teenage pleasures in favour of training.
There are plenty of ways to 'affirm' your own identity which do not fundamentally compromise the rights of others, do those, but don't expect to take a male body into a female sports category.
I only hope sports governing bodies step up to address this.