> The real problem is when others follow Amazon in scale, leaving humans to survive in a new order.
No, the problem is if humans in the set of those who have to work are able to keep ahead of the creation of new automation.
UBI short-circuits the problem because then nobody would need to work. "Who pays for UBI?" you may well ask… well, Amazon can't ship anything when nobody has any money to buy stuff with.
Separately from that, AI currently needs a lot of examples to learn from, relative to humans, so "business as usual" with no further AI breakthroughs will mean lots of people shifting employment every few years. That scenario doesn't force the world economy to choose between UBI and collapsing due to all the jobs being automated and therefore nobody having any money to buy the products made or delivered by the automation.