That assumes that everybody is equally smart and well-informed.

I don't know that it's true, but it seems reasonable to assume that many electric car customers are treating it like a normal car purchase without thinking about obsolescence, and allowing the natural desire to own an object rather than rent it to push them in that direction.

In an ideal world filled with sane, rational humans, buying and renting should cost about the same. But we don't live in such a world.