Just doing nothing isn't great for the "human spirit", but UBI doesn't mean people can't find their own goals to pursue. The idea of something where people are not longer required to work to survive is hard to accept since many people haven't seriously considered how they could meaning outside of their careers
I could ask every one of my coworkers what they would do and they would have a realistic answer.
I don't really have sympathy for people attached to their careers. They did that to themselves.