This, I think, leaves out how much formerly domestic labor has been converted into social labor provided either by the state or market forces. Which could be responsible for a lot of reduction as well, as when one does this efficiencies of scale and rationalization can take place in an organization. I have no idea how or why either aspect would be bigger. Hypothetically, reduction of (for example) childcare hours could be as much about proliferation of daycares and kindergarten and schooling in general as it's about development in domestic childcare technologies. Eating and fix prison is microwaves and McDonald's, etc.