That is not really what happened, that player was playing within a team. She did assisted and combined with other players multiple times, you are stretching your argument ... And believe me, if Messi were playing in the USMNT nobody would complain.
My girls have been playing flight 1 for a few years now, in very good teams. As a result they have played against great teams and players. At times they have been shelled by Galaxy, SD Surf, and the like, and at times they have shelled other teams. I have never thought, not even once, that it was unfair that a particularly good player of their age was playing against them. Rather the opposite, the stronger the opposition, the better. I want them to play against the best players in their age group. If you do not like playing against top teams and great players, that is good too. In my case, when one of them was playing in AYSO and the coach made them use only the left foot to even things up, I realized it was time to move.