As for services increasingly unaffordable by the workers providing them, that's Baumol's cost disease (https://en.wikipedia.org/wiki/Baumol_effect)

I don't have any sources regarding someone preferring humans for certain services over robots, just intuition there, and the fact that consuming human labor and time is itself a status signal of wealth, and the current growth of personal services.

As for connecting the dots, look at Brazil, one of the world's most unequal economies having a small consuming elite and a much, much larger low-wage service underclass. The gulf states as well. Granted, their circumstances don't map cleanly to a post-automation Western economy, but it does demonstrate that a largely bifurcated consumption based economy can exist and can be mildly stable.

Whether the US falls into that direction too will depending on politics. A bunch of mid-career knowledge workers aren't going to willingly to flip burgers in a service economy without some serious surveillance and oppression. But when thinking about it in those terms, the recent push for mass surveillance laws and tech along with the increasingly dangerous rhetoric around protests and "domestic terrorism" start to make sense.