Just assuming that all of these are the equal might hide the actual problem we want to fix. Or might point to asymmetries we might not want to fix.
Of course, the 50/50 gender parity has also a different motivation, trying to address the culturally influenced preference. The argument goes like this: Because of historical reasons, some professions are male dominated. Girls are not interested in these professions because female role models are missing. So if we force the promotion of female role models, this historically created bias will vanish.