I don't think comparing the feelings of female athletes to stroppy toddlers is helpful. Women athletes have a right to a fair chance to achieve success, whatever the level of competition, and not be displaced by males who cannot successfully compete in their own sex class. But hey, suck it up girls, life's not fair, and we shouldn't try to make it so..... not a great message to girls and young women imo. Perhaps you don't have daughters.
Maybe your son gets pissy because he realises he has no realistic chance of winning against someone with such an innate physical advantage as an adult male. It's a shame you can't see the parallels.
I kind of feel you've been putting women down yourself.
You suggested that the women entering the clearly advertised as trans inclusive event did not realise it was trans inclusive.
You suggested that they were too scared after the fact to bring it up.
You suggested that I listen to women.
I did listen to them. I posted quotes from the cis women involved where they said they were perfectly happy with the event and with the result and were upset that it was being used to further a transphobic agenda.
They knew what the event was, they knew what the entry criteria were, they are supportive of their trans colleagues, they are happy with the result.
Perhaps I don't have daughters. Perhaps I do. Perhaps I only think I do.
But whatever the gender of my children, I do try to teach them that not everything has to be ultra competitive, winning isn't everything, and sometimes it's fun to just go out and play with your friends.