It's worth noting that the article that always gets cited every time the Dvorak keyboard gets mentioned, ("Fable of the Keys", claiming that it's a myth that it is more efficient than Qwerty) is based on the near religious belief amongst certain groups of economists that path-dependency of this sort doesn't exist.

They believe we use rockets/Qwerty/Windows because they are the best and the all seeing market has chosen wisely, not because of a series of effectively random decisions and coincidences that occured in the past.