In the days when people worked to survive, they consumed barely less than they produced. That ratio has progressively moved up so that in modern times, the productivity of 1 person supports 5 people. The question isn't how high can that ratio go, which seems limitless with robots and new technology on the horizon; what's important is why should people work at all? The vast majority of people wouldn’t work if they didn’t have to; the equatorial nations of easy food and temperate weather are proof of that. Without threat to life or comfort, people don’t work past life’s necessities; laziness & sloth are apparently the human default.

For several generations, people worked to obtain status & self-gratification but those are subjective & ephemeral things, and require a society that promotes them. When all physical things are universally available, and society no longer fosters a need for conformity, the only viable motive to work would be personal ambition, but that's a difficult trait to understand. Testosterone plays a significant role in making men ambitious & aggressive, but animals have testosterone, and they don't build cities or land on the moon. None of the egalitarian traits of equality, sympathy & envy promote those things either. Inner fulfillment is more religion than fact. Luckily, the primal motivation for men is mating; high status leads to scoring the hottest babes, so men work to increase their status; sex is what makes the wheels go round.