Tragic as this incident was, even if the cars could be made indestructible, unless you can upgrade the human body this crash was unlikely to be survivable whatever formula you run in.
Yes, but the aim of the design of car is not to make an indestructible car (and in fact the destruction of the car around the survival cell is part of how the energy is dissipated to make survival more likely), but to provide a survival cell (by reducing peak accelerations) that enables a driver to survive ever more severe accidents. We will never remove the risk of such an accident completely, but we can continue to reduce the likelihood of such a crash taking someone's life.