Jobs that you want to do vs jobs that you have to do are entirely different levels of motivating and result in completely different energy levels for people.

If I have to do a job I hate for the rest of my life I would eternally be low energy. If I could do the thing I loved every day, the thing I truly wanted to do, I would get up excited every day and would have high energy throughout.

Having more free time, yes people would get bored. But the resulting things that they work on would be things that invigorate them.