The literature is divided. I will point out most of the people you are sharing are not econometricists by trade. And these articles are mostly just saying that

The literature is divided. I will point out most of the people you are sharing are not econometricists by trade. And these articles are mostly just saying that a lot of the cost is due to middlemen. Here is an extremely recent study by one of the most famous econometricists out there: https://www.nber.org/papers/w32606#fromrss https://www.nber.org/papers/w32606#fromrss