Scott Alexander recently wrote an interesting bit on technological unemployment, and the question of whether or not it's happening: http://slatestarcodex.com/2018/02/19/technological-unemployment-much-more-than-you-wanted-to-know/
He concludes that we're not seeing too much in the way of technological unemployment just yet, but we are seeing technological underemployment. The question was raised by this, what happens afterward? What do we do when human labor becomes obsolete?
I personally would reference Meditations on Moloch for such a scenario: http://slatestarcodex.com/2014/07/30/meditations-on-moloch/
What happens in a competition when some participants get an insurmountable advantage and others don't? The ones who didn't lose. In this case, losing probably means falling as far economically as you're allowed to.
That might just mean sitting back on your couch and collecting an U.B.I. while the rich travel to space or whatever - or it might mean finding that you can no longer afford to survive. If, for anything you can make, there's a machine produced equivalent thats better and 1/100 the price... what are you to do? About the best outcome I can see, <i><b>failing societal or government intervention</b></i>, is that you own some sort of property with which to sustain yourself. Land, stocks, whatever.
But thats not something that will apply to everyone, and it won't be a long term solution. Unless you're really lucky (I.E. one of the rich), your property won't be enough to sustain you forever, or your kids, or your kids kids... Eventually the money runs out. So then you're homeless and have no food. Squatting and begging is the next recourse, but that basically depends on the wealthy. If they decide they don't want you doing that, they're gonna send their robot police to tell you to quit it, you're gonna be out of luck.
So what then? Well, your best bet is probably gonna be being sent to prison for squatting or whatever. It's either that or a horribly overcrowded shanty-town on whatever public land remains, and honestly, you're probably better off with the prison. And thats assuming you don't just get killed by the robot police or other unfortunates first. So, yes, essentially. I think the rich will liquidate everyone en mass.
Honestly, I think this is already happening, only very slowly and practically unnoticeably. It's mostly the slow erosion of property, accumulation of debt, slow grinding of people into homelessness, and ever growing wealth and power of the rich.
Now, there are some caveats - some people will manage to tag along with the rich - their relatives, their friends, those offering their novelty as human beings. But I don't think that will be a very large portion of the population. 10%, tops.
Now, yes, that is the worst case scenario. There IS the potential for government or societal intervention. We could implement an U.B.I., or a jobs program, or systematic neofeudal LARPing, or whatever. But on this, too, I'm skeptical. I think there's good odds we could institute something, but I don't think it would last. Unless it was hefty enough to grind the rich back down to scale with the rest of us, and prevent any other accumulation of power and competitive advantage, it would be a purely palliative measure.
In time, the rich would grow tired of it, and begin to wonder "Why are we paying these people anyway? They're basically just parasites. They do nothing useful." (They'd even technically be right.) So they start looking to cut the benefits, cut the numbers of people on the dole, cut the money they personally have to put in to it, whatever. Take all that money spent on education - is that really necessary? They're not going to work anyway. Lets cut that. What about all that money spent on healthcare in the last 30 years of life? If we just have them die early, we can save all of that. What about population growth? If we just cut that, we might be able to stop paying out entirely in a century or two!
By methods like this, the population can be reduced, until the rich no longer need spend anything on the poor at all. So, now that Moloch has claimed his feast, surely now we're done, right? Surely now those who remain can live their lives in peace and happiness?
No, not necessarily. Moloch is a gluttonous god, he is not so easily satisfied. Now, if not earlier, he turns his eye to the rich and looks to play them against each other. Will they compete economically? Politically? Will they turn their machine armies against each other? Will they race for more resources, to plunder and pillage first, and thereby amass more wealth? Remember, it only takes a couple who wish to compete, to pull the entire collection back into the struggle. And yes, they can always cooperate, and threaten violence against any who try such things... But this is not perfect. We have plenty of evidence showing how such measures can be defeated. There will, most likely, still be competition, and as such there will still be winners and losers, and accumulation of power and competitive advantage. And as such, Moloch will continue to receive his due.
But okay, that's enough pessimism. Things might not turn out that bad. Perhaps the rich will be satisfied with their previously-unthinkable wealth, and won't begrudge the rest of us a dole, or perhaps even we'll find that we all finally come together in an embrace of our mutual humanity and everyone sings kumbayah happily ever after. Perhaps we'll become aware enough of this kind of problem, and solve it. Perhaps we'll have our culture/government/whatever lock the rich into some "perverse failure to optimize" that works out in our favor. Perhaps the rush of new resources will be so great, it'll buffer us against such things for several thousand years, or even forever. Perhaps we'll get lucky and find that the things we like and care about are, in fact, optimal, and are selected for, not against. Perhaps we'll advance into glorious posthumans and all of my theorizing will be irrelevant. Who knows. But, as things are, I'm pretty skeptical.