People can already choose to work less for mental and physical health reasons. Just move to a low cost area and do the bare minimum work to obtain necessities.

But people who want a nice large house, luxury cars, new electronics, and fancy vacations are going to have to work harder in ways that might not be optimal for health. Most middle class people seem to be voluntarily willing to make that trade, and you're not going to convince them otherwise.

For society as a whole, growing profits represent an overall increase in living standards (although the benefits are unevenly distributed). If we were to collectively decide that current living standards are sufficient and stop trying to grow then we might have easy, pleasant lives for a couple generations but would eventually be overrun by more growth-oriented foreign societies. Life is a competitive sport and we ignore that reality at our peril. There are more important things than happiness.