Are you trying to contradict Newton?
1. Forces are an interaction between objects.
2. Object A pushes on object B the same as object B pushes on object A.
3. A force on an object changes it’s momentum where momentum = mass x velocity.
Which Newton did you have in mind? Certainly not Sir Isaac Newton. Force = Mass x Acceleration.
When estimating the damage to structures and objects on impact we use energy. The total kinetic energy is dissipated during the deceleration - think of crumple zones on vehicles - and the forces on the structures, objects and in this case passengers depend on the deceleration. If the vehicle and the structure 'crumple' over a long-ish period absorbing energy then the deceleration is lower, the forces are lower and the survivability is better - unless objects are forced into passenger spaces or the passenger compartment is so distorted that the occupants are harmed.
It might be easier to imagine the difference between a crash onto a table of granite versus a crash onto a massive eiderdown, or even trampoline (e.g. as used by fire rescue services). The difference between granite and the other two is deformability, with the deformation absorbing the energy.
Edit: Roseland, our posts crossed, we are saying the same thing