Yes, a larger car is safer, and usually more comfortable to drive.
However, if we started to prioritize our health and long-term survival by mandating that all people must drive smaller cars — and also allocated a special barrier-lined lane for large over-the-road trucks — then the serious accidents associated with larger vehicles impacting smaller ones would be eliminated.
This would obviously not be solved overnight, and might take 5 to 8 years to transition the bulk of the population in a given metropolitan area.
But it can be done, and must be done.
Imagine, if you will, if everyone drove a smaller personal vehicle, with twice the MPG or km / liter ? How much would that increase the quality of life for say, the people of Mexico City, to have half the smog pollution when they breathed in a lungful of air ?