That has literally nothing to do with either what I said, or the thread topic.
I'd like to answer this but it's hard when you claim that the doctor's the one who made the kid female. Aside from a "switch" in the genes, there was no way to know that the kid wasn't female.
My issue with trans people in relation to the male-female segregation in sports is that allowing a trans male in a male team is one thing, but if you allow this, you allow a trans female in a female team as well, and in that latter case, not only will most be able to make the team, but they'll be stronger and faster than the cis women there, knocking them out of the field. And if we stop segregating women and men altogether we have the same problem.
So, shall we be unfair to 0.3% of the population, or 99.7%? That was the point of my post: not everybody can walk on the moon even if they really, really want to.
Here's the thing though.
If 0.3% of the population is trans, that means maybe half that number are MtF, so we're looking at .15% of those, how many will want to be in sports?
Women in general are less likely than men to participate seriously in competitive sports. Can't find a number, but I'm guessing it would be generous to say that half of females as a baseline actually are involved in serious competition.
So we're down to .075%
From that, trans people tend to be pretty self conscious of their bodies, MtF trans people often flock to stereotypical feminine behaviors to help bolster their challenged identity, that lessens the number more, hard to even guess the numbers.
From that you have a very small number of MtF young people who might pursue seriously competitive athletics. Now, within that group, some will be within the physical range of their cis female competitors, some might be beyond it. The ones who are within the range aren't a problem any more than tall or especially muscley cis females are a problem. The ones who are to a significant degree outside that range, well if they're like most young women, they're likely to feel self conscious about being perceived to win unfairly, and that would lead a fair amount of them to not want to compete in that arena.
What we're left with is the tiny amount of MtF young girls who want to compete with their cis female peers, have bodies that make it significantly unfair and no particular awareness or social care about that.
It's sure to happen, but it's also overwhelmingly likely to be an extreme rarity. The number of people affected by these competitions would be pretty low, not 99.7% of the population by any stretch.
In fact, given that sports is seen as normative for boys, while numbers would be impossible to find with any certainty, I wouldn't be shocked if the number of FtM trans boys who want to be a part of boys competitive sports exceeds the number of girls who have any possibility of being adversely effected by competing against a MtF girl.