Well, it is a utopia. Asking the UN to approve a complete shift of the way in which we measure time would be enormously disruptive.
There’s also no way to enforce mandatory lethargy, because you create an economic incentive for every company to cheat in order to beat the competition. It’s just not possible at all. But it would make for a nice poem. Zero pragmatism in this concept though. It doesn’t take into account human nature, incentive structures, or anything else needed to actually implement this. It’s game theoretically unwise to say the least.
Mid recommend reading Tainter’s book: the Collapse of Complex Societies. You’ll get an understanding of what we’re up against as a species and what’s actually required to steer this massive ship.