Are you not aware that personal consumption expenditures have been on the decline this entire century so far? In fact one of the reasons retail is dying is not just Amazon, it's a lack of spending money. Wages have been stagnant for decades while the cost of basic needs have been going up. As a result people have less money to shop with, and subsequently economic growth has been slowing.
You should do some reading up on this. It's pretty much already the new consensus that inequality has grown to extreme and is holding back the economy. We are looking at a growing crisis of demand, not supply.
RE: Why inequality is growing so extreme and how Alaska points the way to the solution