4 day work weeks were predicted way back in 1960. The nearest I ever got to it was a 10 hour work day, four days a week. OT on Friday and Saturday.
It won’t work at some jobs. Try working a 4-day work week at a commissioned job & see what it gets you. Broke, most likely.
Yang’s proposals come from thinking that, because you know one business, you know all businesses and are qualified to decide what everyone else should do.