The US Men's U-17 team is not a high school team. It is a team made up of world class athletes who are high school aged. That is a huge distinction. You are saying a team a world class men can beat a team of slightly older world class women. That isn't surprising.
The US women's team is best in the world, US men's team doesn't even come close to being best 20 teams in the world. They are high level athletes but not world class (especially for soccer) by any sorts.