Once again a decent sensible post. It does seem from this thread that there is a massive lack of empathy and understanding about a group of children/teens for whom life is already extremely difficult and confusing.
Everyday, in one way or another, it is pointed out to them that they are different, too young to understand themselves and don't fit in with society's norms. The sporting argument (for which I don't have an answer) is often used as just another opportunity to emphasise this.
It seems that unless you know a young person going through this, then it is too difficult to try to understand the pain and the vulnerability they feel. The world can be a very cruel place and language and empathy become extremely important.
The pile in on
@maniak in this thread, mostly, ignores both those and feels particularly harsh, and though I don't necessarily agree with all he has written, the base of his argument is inclusion which seems to me to be an excellent place to start.
Seeing someone's difficulties used so openly in culture wars on both sides of the Atlantic has a huge impact on both physical and mental wellbeing. The left handedness graph is a brilliant analogy and one I have used with family and friends to explain why gender dysphoria may appear to be more common today than it was when they were kids.