... Even where capital accumulation is concerned, I am not sure that Piketty's theory emphasizes the right aspects. Looking to the future, my guess is that the main story connecting capital accumulation and inequality will not be Piketty's tale of amassing fortunes. It will be the devastating consequences of robots, 3-D printing, artificial intelligence, and the like for those who perform routine tasks. Already there are more American men on disability insurance than doing production work in manufacturing. And the trends are all in the wrong direction, particularly for the less skilled, as the capacity of capital embodying artificial intelligence to replace white-collar as well as blue-collar work will increase rapidly in the years ahead.

Where does this leave policy?

Piketty's argument is that a tendency toward wealth accumulation and concentration is an inevitable byproduct of the workings of the capitalist system. From his perspective, differences between capitalism as practiced in the English-speaking world and in continental Europe are of second order relative to the underlying forces at work. So he is led to far-reaching policy proposals as the principal redress for rising inequality. ...

Thomas Piketty Is Right About the Past and Wrong About the Future
Capital in the 21st Century deserves all of its praise, but it should not serve as gospel on inequality.
The Atlantic