The concept of "post-automation" makes no sense. Automation is an eternal exponential curve that's been going on for ages, there's not going to be a discontinuity unless we suddenly discover something magic.
I think this is Yang's biggest fallacy. He assumes that growth and innovation will be "eternal exponential". That's a pretty huge assumption. Yes, it's been relatively true for 100 years, but that's a very small slice of human history. What if growth isn't exponential? What if the singularity is 1000 years away?
Moore's "Law" and exponential growth are taken as gospel, but there's no reason why it will continue this way forever. Too many people are thinking about the singularity and too few are thinking about an impending innovation stagnation.