Wrestling a girl is a “no win” for the guy. If he wins, “So big deal you beat a girl.”. If he loses, “Ha..Ha.. you got beat by a girl.”
But more fundamentally, I think forfeiting shows respect for the difference in gender and it is the right thing to do.
That is how we both felt. I gave him credit for knowing how things work at such a young age. He respected girls and still does! Gets his heart broken cuz of it but.....