"Minorities" have always been a bad term for the real issue (was the plight of black South Africans somehow less real because they were the majority?); if you think that women aren't a group that has been, for an extended period of time in the US, subject to both informal and, (at a minimum) until fairly historically recently such that it still has a substantial impact on attitudes, overt and formal discrimination, then you haven't been paying much attention.