The same thing as any other labor shortage? Employers offer more money, and people who want that money apply for those jobs?

How is society supposed to function without an underclass of poor and unhealthy wage slaves?

Yeah! Who's gonna deliver my groceries?!

I recommend Neal Stephenson's Snow Crash ... tl;dr: guys with katanas and kids on skateboards with really cool tires and grappling hooks ^^

that's exactly how! self-interest. being lazy is always up there as an option. some people button-mash that shit the minute they wake up. and not all of them are poor, unhappy, unhealthy. it's usually only when other people feel the need to remind them that they can press pause and the check the list of available commands to which they usually answer something like: "no shit, sherlock", that they suddenly feel inadequate and stressed.

Yes, that’s a feature. But it’s also discussed in the context of AI creating a massive/total job shortage. The timing is the tricky part, as job shortage grows maybe it would even mean lower minimum wage.

i doubt that min wage workers will all quit, the extra money is what they need to live properly

Right now workers do those jobs, because if they don't, they will die or become destitute. If you change their incentive to be they can work an unpleasant job while rent and food is guaranteed, you're going to find that the marginal value of that 12 euros an hour has plummeted. It's not worth it to work a terrible minimum wage job if your basic needs are satisfied

it's still not enough to raise children, for example, or buy a car, or get more culture. you need that extra money and it will be easier doing that shitty job if you get enough time for variety and your bank account statement doesn't raise your stress levels.