You're kind of sweeping over decades of sexism here
Women have always been discouraged from going into fields like math because we were taught we are not smart enough or that it's a "man's field" and women should do easier, feminine things like the arts. Even today women who have interests in maths or engineering etc. feel a lack of support from their male peers if they do decide to pursue it. It really is an uphill battle being a women in these male dominated career fields. It has nothing to do with women being less intelligent and everything to do with purposely trying to keep women out of these fields, because the thought of a woman being just as or even more intelligent than a man was terrifying!!!11
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