Lol, I think "flow guy" works.

Exactly. When the physiological needs are met (which UBI in theory would take care of) then it changes the game from "what do I have to do" towards "what do I want to do."

While this really is a much tougher (and changing) question to answer, this tends to put people working towards things they are truly passionate about. Of course at the beginning there is a 'learning curve' that anyone would have to overcome, this would normalize into states of flow whether in action (music, games, etc.) or curiosity.

There would still be the difficulty of 'society' having all the bases covered (such as x amount of food still needs to be produced and available,) but at least people would be doing what they do with maximum effort.