Changing your political regime gives you UBI. That's literally the only way to get UBI. It's not gonna happen magically by itself.

I guess at the pleasant end of the spectrum we end up with something like the Culture - where meat-based citizens are treated with indulgent care by the god-like AIs leaving us to do the only thing we'd be uniquely good at: having fun.

At the other end of spectrum we are either deemed irrelevant, a nuisance or abused for eternity in the simulation spaces of evil AIs (see "A Colder War" by Stross or indeed works by Banks and Vinge that describe particularly unpleasant possibilities).