That will mean that most small teams will fail, as they will be composed from average developers. While a few teams will succeed as they have the "extraordinary", whatever that means, developers.

But the reality is that big teams have problems independently of the capacity of the companies to attract talent. So I don't think that "average ability" is the source of the problem.

As someone else posted, The Mythical Man Month is a good read on this area. And communication overhead is an unsolvable problem as the people involved intro a project grows.