That's not because the argument is difficult to lay out — it's because the evidence to support it is so prodigious, and because Piketty predicted (correctly) that showing that capitalism produces dynastic, multi-generational fortunes, rather than a dynamic, meritocratic rags-to-riches system that rewards prosperity-creating innovation would attract vicious assaults from the mainstream of economic thought.
Much of Capital 21C is aimed at heading off those critics at the pass, retreading the same arguments over and over, from different examples, making them unassailable as possible.
This is important — because Piketty has something important to say, and it will only resonate if it can't be easily dismissed — but it also scares off people who would benefit from reading Piketty's work but don't want to commit to months of slogging through a brick-sized book.
In other words, Capital 21C needed a Ted Talk — and now it has one.
(via 3 Quarks Daily)