Notice that no one ever cites any sources for this. There's numerous sources that say 70% of people aren't motivated at work -- including one by Harvard of 1.2M Americans.
I think Americans have this idea that they would like to do /something/. But for most people, that's not what pays the bills, or what they're qualified to do.
A lot of people say things like, oh, if money wasn't important, I'd be a teacher or a nurse or something more social. But usually the more critical price is they don't want to go through years of training to be a teacher or nurse or guidance counselor or what have you.
A lot of people say they'd start a business, but UBI isn't going to provide enough capital for everyone to run their own bar or restaurant or boutique hotel. And someone is still going to have to wait the tables and clean the rooms.
It's a utopian fantasy.
https://employeebenefits.co.uk/third-employees-poorly-motivated/
https://hbswk.hbs.edu/archive/why-your-employees-are-losing-motivation