“When the rate of return on capital exceeds the rate of growth of output and income, as it did in the nineteenth century and seems quite likely to do again in the twenty-first, capitalism automatically generates arbitrary and unsustainable inequalities that radically undermine the meritocratic values on which democratic societies are based.” ― Thomas Piketty, Capital in the Twenty-First Century
This outcome is probably clear to anyone who has been paying attention, but the power of Piketty's book is in the way it lays out mathematical proof using pile of historical data as evidence.
The response to Piketty's book from ideological opposition have ranged from "So what?" to more valid attempts at asking theoretical questions about the validity of r > g, but nothing exactly that comes close to debunking the core thesis.
Which coincidentally was a basic insight behind Karl Marx's communism -- not referring to the regimes it inspired, but to the idea that with the advancements in capitalistic production, distribution will be key to ensure a fair society.
In the end, a powerful 0.1% that can produce anything they want with robots, can use a small number of humans, say 0.9%, for service and such necessary jobs, and will have no use for the rest 99% of humanity -- which could be let to sort it out in slums.
Also the idea behind lots of dystopian fiction -- from Soylent Green to Elysium, and the reality in many places in the third/developing world, where there are more people than jobs needed.
Suggested reading: https://www.amazon.com/Planet-Slums-Mike-Davis/dp/1784786616