I think studies show that women spend nearly as much time on domestic chores as ever.
Yes, washing without a machine was a long and laborious task, but it may shock you to learn that people didn't wash 1-2 full changes of clothes a day in the time before the washing machine.
Bunkum. I'm old enough to remember my mom leaning over the bath scrubbing clothes on a washboard for a family with five children. Her first automatic washing machine was a godsend. Now with families getting smaller I have my doubts about your studies.