I've never understood the illiberal desire to treat boys and girls so differently. I'm glad I live in a country where sexism is illegal at a fundamental level -- this kind of law would be quickly struck down.
Which country is that?
This sounds crazy, I know, but perhaps boys and girls are different.
Maybe it's based on millions of years of biological differences in their capacities and functions (starting from body strength and role in reproduction), plus differences in social roles, of which some of the latter might be arbitrary, but some are necessary adjustments every historical society understood.