The argument often used in these bans is that athletes who have been exposed to testosterone during puberty have greater muscle mass and therefore an advantage over women in women's sports.
I wonder how much testosterone exposure and resulting "muscle mass" is evident in these 15-year-olds? The article doesn't state if they were on puberty blockers or T-blockers, but that would be a factor.
In the words of Pink Floyd, "Hey, Teacher! Leave them kids alone!"