Even in sectors where technology brings more efficiency and productivity, shorter workweeks could harm the economy. : Billionaires and Bernie Sanders agree on at least one thing: They see a four-day workweek in America’s future. Hedge fund manager Steve Cohen is investing in golf courses because he anticipates a big increase in leisure time, and IAC founder Barry Diller is expecting people to be in the office only four days a week. The senator from Vermont, meanwhile, has proposed legislation that will set the workweek to 32 hours. Put me down as skeptical.