Are cars overbuilt?

I was chatting with a colleague about how long modern cars last, when it occurred to me that today's cars mostly die of trauma. It doesn't matter that a car will run for 15 years; given our aging drivers it'll be smacked within 10 years.

So are cars overbuilt? Should we be buying cars based on the costs of replacing body panels? A side blow to a van with motorized doors may be prohibitively expensive to repair, but a van with manual doors might survive the same accident.