If you want people to be able to work 15 hours a week and have enough to make ends meet- I think most people would jump at the chance, but capitalism is not the right economic system if that’s your goal. Capitalism is a machine that maximizes returns on investment; having people only work 15 hours a week doesn’t do that.

Also, there’s a hidden assumption in there that child care doesn’t count as “work”. A child needs 16 hours of care and attention every day and no economic system can reduce that.