I have read the book, and found it frustrating for the same reasons I mentioned. For example, the core concept of System 1 vs System 2. He says somewhere in the book early on that they aren't actually "systems", i.e. a physical brain structure. But then he uses language like "System 1 does X and System 2 does Y," implying there's some grounding in neuroscience, when there is in fact none. They are just a grab bag of functions that don't have much in common, but we're led to believe he's describing something fundamental about the brain.

The other thing that annoys me is his pessimism and nihilism of seeing human beings as fatally irrational. One response that I found interesting was the book The Enigma of Reason by two evolutionary psychologists who argue that reason evolved in humans specifically because we are social animals, and the purpose of reason is to persuade others. It's why we are so much better at catching other people's poor reasoning than our own. The implication is that reason is designed for group settings. Showing that isolated individuals reason badly is like riding a bike on an ice skating rink and saying the bike sucks. We test human reasoning in conditions its not designed for and then come away with an overly pessimistic view of humanity.