There’s nuances here, but in principle you are incorrect. A car can be assumed to be infinitely heavier than a pedestrian. That means that every part of their body that’s in contact with the car will be accelerated to car speed. So it’s not that with a larger area the force is spread out, there’s actually just more places that have force applied. In other words, a low car will break your legs, a high car will break your legs and torso.