There are always some that will “do nothing” if given the freedom to live as they want. Most won’t. What exactly will take the place of a 9 to 5 in a post Capitalist world? No idea. I’m not that smart. Humans do need more than simple pixie dust and altruistic motivations to do more than the most bare bones of things. That said, whatever the next system may be, it need not threaten peoples security (housing, food, and medical care) to be functional.