> The productivity growth from such new technology would induce more consumption

Whose consumption? There is nothing impossible about a scenario in which there are about 2-3 millions of owners of fully automatic businesses and/or landlords who, with their total output combined, produce more than enough of anything needed for, or desired by, 2-3 million people. The only problem is that the rest of humanity would have to somehow disappear to not sullen this perfectly harmonious market economy of entrepreneurs (which is ironically quite similar to Adam Smith's naive descriptions of it in his own times), but we do have negative fertility rates, after all.

So there is absolutely a path where the well-to-do will just switch to trading with each other, with aggregate output shrinking to match the shrunk demand, and the rest of people could go and drop dead or whatever they want, as long as they don't trespass on the private property. After all, most of what those losers would have would be their ability to work but it just won't be priced competitively: the fair market price equals marginal costs (which for labour is the price of the subsistence minimum), and if robot maintenance is cheaper... yeah. To quote on of the designers of the shock reforms of 1992 in Russia, "what do you care for those people? So, 30 millions will go extinct. They failed to fit into the market".

The future is looking a lot like the movie Elysium, with a few million owners doing all the commerce, safely segregated away from a few billion have-nothings who are barely economically relevant.