A lot of safety features when driving don't exist because of perception more than anything. There was once a push to have car drivers wear helmets. The car lobby instead lobbied to have bicycles wear helmets to change public perception. The truth is wearing helmets in cars would save exponentially more lives than on bicycles. They ended up on bicycles to make people feel like car alternatives are dangerous, even though nothing we do day to day is more dangerous than driving a car. A five point harness is probably a good idea, it would just never get past the car lobby. They don't want people to be reminded that they are driving coffins.

Your example was not a good one because it misunderstands why we don't have those things.