Author here. My argument in the OP was that we maybe would never need to transition. With 36-bit addresses we'd probably get all the people and devices to fit. While there would still be early misallocation (hell, Ford and Mercedes still hold /8s) that could probably be corrected by buying/selling addresses without having to go to NATs and related. An even bigger address space might be required in some kind of buzzword bingo AI IoT VR world but 36 bits would be about enough even with the whole world online.