It's true that he could have cited more specifics, but they're not hard to check. Indeed, for a rich source of hilarity, you can just check out the list of Nobel prizes in economics.

For instance, Shiller got the 2013 Nobel Prize for pointing out that market volatility was way higher than you'd predict from an efficient market hypothesis, and that you need behavioral economics to help explain why. EMH has been hot stuff since the seventies despite failing a bunch of empirical tests back in the...sixties. It's good to see that there is the possibility of progress, but it's incredibly slow.

Card, Angrist, and Imbens won the 2021 prize by pointing out that you can look for situations in the real world that have an experiment-like structure and interpret them as experiments (+ math to make sure it's correct). So you can test hypotheses! Amazing! Especially since ecologists have been doing this since forever? Better late than never, I guess. And is this standard practice now? (Hint: no.)

Since it takes only relatively superficial examination to find examples of Benjamin's claims, it's not too problematic that he didn't give many specific examples himself.