Who the hell is "They"
And UBI is not some sort of demonic plot. But people thinking ahead to what will happen in the AI revolution. Which is 90% of people will go out of a job
You should never overthink ahead when you don't know what will happen. AI revolution is not something that will go over night, there will be many things AIs probably won't be able to compete in with humans for a very long time. And when we do make AI it will take time to scale it in order to make human contribution unnecessary. Chances are that those 90% of people would just find another job. Most likely most of them would change their jobs to the ones those 10% have and others might go more into art or something like that. You can always have a job to monitor AI, to make sure everything is going as intended and then pay people for that with the money we get from AI's jobs.
90% of people lost their jobs before and they just made new ones. Once almost all of the population was employed in food production, farming,hunting,fishing,... But once machines came to be, they all lost their jobs. But that only freed them to do other jobs, like sciences, engineering, art,...
Having more workers or doing jobs more efficiently is never a problem.
