Why do you find them absurd? I read the article below (linked) which gave quite a bit of information (I didn't have/know).
I do think there should be equitable treatment of boys/girls, so if the boys can then why not the girls? Girls mature (physically) earlier than boys, so if boys are making prof debuts at 16 or even 15 in leagues around the world, up to and including the elite leagues, why would a girl not be capable of the same?
The age restriction doesn't actually make sense from a playing or competitive perspective, which is basically what the judge is saying.
It may be moot if the players and league agree to insert it in the collective bargaining agreement, per the article.
U.S District Judge Karin J. Immergut Monday granted a temporary restraining order, requiring the National Women's Soccer League to lift its 18-year-old minimum age rule for players while it negotiates a contract with the players association.
www.oregonlive.com