3. Pretty soon I'll be able to make my own cheap crap.
I haven't seen a single public source acknowledge what the mathematicians (particularly fans of John von Neumann) must certainly know by now.
We are quickly approaching the steep part of a hyperbolic manufacturing curve, as self-replicating 3D printers become a reality. Faster than anyone seems to guess now, the need for exported goods is going to disappear virtually overnight as local manufacturers gain the ability to build any part within beautiful tolerances, limited only by raw materials, power, and for awhile after that, human assemblers.
The big-boxes will die out quickly, because consumer products will be built within the home or at corner manufacturing shops. There will be no storage costs, no shipping costs, and the products will be tailored to the precise needs of the local population.
But the big-box buildings will be highly valuable to local manufacturers, so I expect the parking lots to still be crowded with people. But they'll be there to make money instead of handing it over to filthy rich corporations. Don't worry about them; they'll still find a way to steal a slice of your pie at every stage, but they won't have us by the balls like they do now.
If you've got a kid, you might encourage that child to look into mechanical engineering. Someday soon, the engineers will again rule the world.