https://www.cbssports.com/soccer/news/a-dallas-fc-under-15-boys-squad-beat-the-u-s-womens-national-team-in-a-scrimmage/

The US Women are some of the most physically and technically gifted women in the world, and they were blown out 5-2 by a club teams U-15 squad. It's just biology. 

Like John McEnroe's comments on Serena competing with Men. She's the most dominate female tennis player in the history of the sport, but she'd struggle to crack the top-500 if she only competed against men.