This is just a guess, but my guess is that although gender differences are not so important in today’s world, even back as early as the 80s I as a child saw gender roles in my parents. Dad went to work mom stayed home. Go farther back and those things become stronger yet I believe. I think gender had a much stronger influence on ones mindset then it does today. Now people are okay when other gender identify as the opposite sex. Back then I have no doubt there would have been gender biases.