You are ignoring the huge difference between "teams are choosing the optimal QB" and "teams make decisions no better than random". The decision is neither perfect nor random.
This is getting far afield of the original critique. The point there was that scouts do a good job in selecting QBs, especially for picking the best QB (first!) in a given draft. There is very little evidence to support that claim.
Surely, selecting the top college QBs in the country isn't random. But selecting among that echelon appears to be, especially for the transition to the NFL game.
