You're rather missing the point; AI will create a shortage of work to do. The alternatives you mention aren't things that pay a living wage so yes, people will be without livelihoods and something akin to UBI will be necessary.
Real AI would create mass unemployment, 50% or more of the population unable to find someone to pay them enough to live on because robots will be doing all the jobs they're capable of. How are these people going to survive? That's the issue being discussed.