The US has been overbuilt in retail space for a while though. That's not new. It's just coming to a head because people's income isn't growing.
Realistically folks work a lot more for no more money. Because of that we will see people start to reassess what they value. Experiences are starting to matter more to people. And we are seeing an early shift away from mass produced consumerism to a focus on having less things. What people do purchase will be better quality.
Retailers will either have to play to offering a good experience and quality goods. Or they will have to be cheap and convenient. On the cheap and convenient side of things, you better be ultra efficient or you can't get there.
The question is, can Walmart lean out enough to go back to being cheap? I don't know. The issue is that their stores are too big for ultra efficiency. And half of them are filled with cheap quality apparel/general merchandise that people are going to want less and less. So how do you get ultra efficient/cheap in food if people don't want to shop the other half of your stores?
Walmart's problem is what has happened to the middle class. As the middle class has declined, it's put a beating on their fortunes. I hope they figure it out. We are all in big trouble if Walmart goes down.