I have taken one of the central tenets of Piketty to be that institutions are central to the determination of wealth and income inequality. The "laws of capitalism" act on capital ratios and even the capital share of income, but given an institutional environment that determines r (in conjunction, of course, with technology itself). And certainly institutions determine wealth and income distributions more broadly.
That's like the one thing that he says over and over and over again: institutions, institutions, institutions.
But Acemoglu and Robinson have a review out that seems like it has a lot of interesting stuff on the focus on the top shares, etc., but that centrally claims that Piketty doesn't think institutions matter.
This seems really strange to me.