Well thought out post .... so are you of the opinion that machines / AI will be the source of artificial 'food' created with optimum nourishments etc. ? Or will good old agriculture be required ... planting, feeding, harvesting all to be done by robotics? What of pesticides, pests, the good old bee?
For me the idea is too far fetched, although I am fully onboard that automation and AI will continue to grow in the future and play an important role but more in 'lifestyle' technologies like VR, Metaverses and medical procedures. That what you envisage is more something that should be pursued by Elon Musk for his Mars settlement.

As regards UBI I think that is a dystopian poorly thought out construct and will never work. The Divided States of America is a perfect example of this. There are millions of Americans who do not want to go back to work because they are receiving more from the State than they would from their employer...

Human basic truth.... the majority of the population 'if their is no incentive to produce..they will not produce.