You're looking at things from the viewpoint of society. There your argument makes sense -- of course "people" will continue to work. But that argument, that we'll just continue to work on things higher up Maslow's hierarchy, doesn't hold for individuals who don't hold an ownership stake in these technological advances. Robot Mega Corp and it's owners have no need for your grandmother's scarf, so what is she going to provide in trade for her more basic needs? Not having a job could be a real problem for her.
Incidentally, minimums, where earnings less than $X are increased to $X, are terrible and break incentives near the minimum. Much better are base incomes, guaranteed uniformly to even the wealthy.
> Robot Mega Corp and it's owners have no need for your grandmother's scarf, so what is she going to provide in trade for her more basic needs?
This is assuming that the robots are owned by a monopoly or a cartel. Such a case is an obvious candidate for government to step in and break them up.
On the other hand, if the robots are owned by companies that aggressively compete with each other, how much do goods cost when they're made by robots using robot-produced raw materials? The more humans we replace by robots, the lower the cost of goods will be and the easier it is for charity or government to provide them gratis to the public.
Yes, I don't think I phrased it well, but I didn't intend to assume that there is a single Robot Mega Corp.
> The more humans we replace by robots, the lower the cost of goods will be
Most physical goods have two parts: materials and labor. Even if robots were to bring the labor cost to approximately zero, we still have the material cost. So you're right that you don't necessarily have to own the robots to successful, but you do have to own resources.
Even "resources" primarily only cost money because of the labor it takes to discover them and then remove them from the ground and refine them. In theory there are some things that are genuinely scarce (e.g. energy or specific elements) but so what? Most of them have substitutes, and the fewer labor costs have to be paid the more substitutes become viable. Have the robots mass produce wind turbines or solar panels out of low-scarcity materials, or mine space, etc.
Even in the most pessimistic case where you have a valuable scarce resource with no substitutes then you have something to tax which will produce revenue that can be used to supply necessities to the public.
Incidentally, minimums, where earnings less than $X are increased to $X, are terrible and break incentives near the minimum. Much better are base incomes, guaranteed uniformly to even the wealthy.