Why are people so anxious to erode gender norms?

In most cultures, throughout most of history, there have been well defined gender norms. Men did the fighting, manual labour, and the running and organisation of their spheres in the community and wider political landscape. Women took care of children, their household, supported their men through difficult times, and gave balance to the hedonistic tendencies of men. In more recent times, women also took on certain jobs that are better performed with a woman’s touch.

However over the last several years, concepts such as quotas and affirmative action have skewed the marketplace of skills so that women are given an unfair advantage for acceptance into male-dominated roles, and emasculated men are drafted into female-dominated roles. While of course if a woman is better at a certain role than a man (whether it be secretary or CEO) she should be given that role, surely intentionally selecting a worse applicant based on gender is destructive?

Additionally, there is a growing trend towards failing to teach children gender norms. Pink and blue are out, and girls are given diggers to play with, and boys are given dolls. What good could possibly come from this? Should we not be fighting against gender discrimination, rather than simply promoting a different form of it? Why should we reject a model that has served us well for thousands of years, and presumably evolved for a good reason?