This part of your scenario goes far beyond what I comprehend to be the concept posited in this hypothetical. This is at the level of star trek replicators, not simply increasing the efficiency of our manufacturing to fully automated, robot-controlled levels with no human involvement.
We aren’t going to have people fabricating stuff at home simply by making fabrication of stuff more efficient. Acquisition of raw materials, transportation, refining them into more usable raw materials, transporting them again, converting them into even more usable forms, probably yet another level of transportation (or several more levels of both transportation and production), and finally fabrication of the finished product will still exist.
Making things will still require factories for the foreseeable future, regardless of how much automation we get. As far as I know, energy to matter in the form of star trek replicators is considered scientifically improbable, and similarly some kind of ‘omni-gel’ type substance that can be instantly fabricated into whatever is also improbable (although far more likely with a limited set of possible things to produce). Therefore, no, people won’t be creating their own stuff at home - things will still be mass-produced in factories, they’ll still need to be transported around and people will still have to go to stores or have them physically delivered to their homes.
Now, the first part of your post that I didn’t quote makes some sense. I can see that potentially happening, maybe. If the manufacturing process is cheap enough, and there’s enough competition to drive prices down to near-cost, rather than allowing the manufacturers to simply make ever-higher profits as costs go down, then maybe that vision would happen instead of mine. It’s still pretty similar in the end, with the hyper-elite pushing everyone else out of their elite enclaves, except now they’re providing a basic living for them in order to keep them from revolting. That might very well be the more likely scenario - I’m not sure.