Hair stereotypes

My husband is perfectly fine with our son having long hair but won't let our daughter cut her hair short because she's a girl, he said quote "my daughter is not walking around looking like a boy"

Meanwhile our son had long blonde hair and super long lashes and frequently got mistaken for a girl but it didn't bother him 🙃 my take is you can't have one rule for one child and one for another. Opinions?