Agreed. Think it would happen, though?
It seems to be the way they do it now, but legacy network assignments are the problem. The RF spectrum is the same way: HUGE swaths of bandwidth are owned by the government or the railroads, due to decades-old deals.
They are nearly all unused, but off-limits to everyone else.
I would support a one-time audit of class A licensees for determining their actual internet-facing node count and reassigning address space accordingly. Millions of unused addresses would be freed up.