And prior to the Women’s Liberation movement the huge influx of women in the workforce was inconceivable.

Thank you for proving my point and refuting your own. Shit happens that we “see no impetus for”. In the 1970’s who would have forseen legions of “Super Enginerds” with incomes between $100 and 200K proliferating SD? Whats next….we will just have to wait and see. In the absence of anything else, all it would take is time and inflation.