I'm not up to date, but when I knew about this stuff the cost of memory for routing tables was only a tiny, tiny fraction of the cost of a network. Most of the cost is burying and maintaining fiber.
So unless something big has changed, it seems like a terrible choice to twist the whole system into uselessness to try to save a small amount of RAM cost.
So unless something big has changed, it seems like a terrible choice to twist the whole system into uselessness to try to save a small amount of RAM cost.