Maybe we have a different look on basic income, for me it's like unemployment money with less steps and less overhead (less bureaucrats). I also dont know why you pull in marxism, but those systems normally starve because of bureaucrats (hello germany) where you have to fill out 10 papers to create one praline, and NO i dont say germany is "marxist", but they are really good at always taking the worst from both sides.

For giggles, lets say every work can be done by robots, every service by ai and energy is free (dyson sphere or whatever you want), who's left to spend money and for what? And tadaa StarTrek ;)