Similar arguments could be levied for racial stuff, and I'm pretty sure were used to justify segregation eg: in combat units.

"Different races are strange for kids, it may cause them stresses firing off their innate biological danger senses, maybe best to keep 'em separate if the other task at hand is too important"

The only thing required to challenge the status quo about a discriminatory practice is the absence of proof. I don't agree that I need to do extra legwork just because I want to change things up.

However, I'm Canadian. And in Canada, scouts don't discriminate. So I don't really have to do anything, other than explain that the American attitude towards this seems very backwards to me.