That's the big question about automation that I always ask that just gets handwaved away with "We'll pay a lot" or "People will want to".
There's going to be a job gap, if there's not one now, where we have far more people than jobs that are needed.
So the answer for the unemployment situation is basically accepting the post-scarcity nature of the world and just kind of let people live. No means-testing, no qualifications, just people getting X because it's the right thing to do.
So how do you get people to do anything they don't want to? How do you get people doing the jobs no one may want to do but will need to be done?
Right now the system is rolling due to inertia and the promise that this is temporary. Just because something can be tolerated temporarily, it doesn't mean we can sustain it indefinitely.
And I'm not saying things should stay the same. I'm saying that we are not prepared for the changes that are coming. We do not know the answers to the questions we're about to face. It's going to get difficult.