Intel actually has very few designs. Most of the variety comes from frequency binning and post-test functional unit deactivation as a means of salvaging otherwise defective parts.
Same as with "peak oil" then. Its not that we run out of physically extractable oil, but that the cost of doing so will curtail our current usage of the substance.
Its pretty much the inverse of the Jevon paradox (or maybe that everything has a bell curve, and we are so focused on the left half we forget its mirror on the right).
Actually, people are looking forward to a long period where a certain node, "20" something nm (not Intel's 20 something), becomes so standard that economies of scale result in it being the one most entities use for their designs, especially non-mobile or otherwise seriously power constrained.
I gather we're already sort of there, with wafer costs in the $5,000 or so range, the trick is of course to limit the NRE to something you can afford. The lowRISC project is going this route, I learned much of this starting from their future production plans.
It may well be that economics is the limiting factor stopping Intel's long run, not the physically limiting properties.