I don't think it is really that hard. Wearing a tie is impractical, as is wearing really tight pants. I honestly think the reason pants took over has nothing to do with gender equality and more to do with it being less difficult to match colors with clothing. My wife spends forever matching stuff. When she wears jeans, she takes forever divided by 2.
So, I think all that's needed are PODs that make pants really undesirable from a fashion standpoint. Perhaps a longer world war 2 and women did even more work in factories, so pants get this image among women of conveying that the wearer does physical labor?