Ideally, a vehicle structure should collapse gradually with increasing force so that its occupants suffer as few "G"s as possible. The collapse should store the crash energy, which is what it does by plastic deformation. I've known people who have survived high speed crashes- one walked away from a 200 mph crash and another who lived through a 432 mph crash but suffered brain trauma. These drivers were in strongly-built race cars with racing harness restraints and wearing SFI helmets. Ordinary drivers would never be so well protected on the street and there is a limit to what can be done to protect a street vehicle occupant above only a moderate speed. These tests do not produce anything of engineering value but they do provide videos for the "speed kills!!!" zealots. Similarly, there would be no value in taking videos of an airplane diving nose down into the ground.