There's another explanation, that they have the capacity to drive price of entry up. That they have enough money saved that they can undercut their competitors

There's another explanation, that they have the capacity to drive price of entry up. That they have enough money saved that they can undercut their competitors and snuff them out before they can gain any market share. So this is true whether they are efficient or not. However I'd argue the damning blow is that centralization makes efficient but fragile structures. Its why everyone hates a monolithic codebase.