It just occured to me...why didn't we have large scale commercialization of space already? And I had a strange answer:
The microchip and the fiber optic cable.
One of the few killer apps for space satellites was the communications satellite. But the microchip allowed multiplexing many voice streams onto a single high bandwidth signal, and the fiber optic cable made cheap long range high bandwidth communications possible.
What might have happened if the microchip and fiber optic cable weren't developed for another few decades? We might actually have needed hordes of communications satellites to keep up with global demand. That means a solid customer base for launchers, and that means mass produced launchers and/or big dumb boosters.
Without the microchip, these communications satellites suck up all sorts of juice. Thus, there's a huge incentive to develop efficient solar cells. With advanced space rated solar cells and cheaper launch technology, space based power may even be practical.
The result? Large scale industrialization of space, and sufficient economies of scale that launch costs are relatively cheap.