No, I mean that many motorist lives would be saved if they all literally wore helmets. They should be required to. Airbags and roll cages help, but they are (obviously) insufficient on their own to prevent the 20k car deaths every year.
It would also help reduce the 200,000+ TBIs (traumatic brain injury) caused by car accidentals in the US every year.
I might be convinced to personally start wearing a helmet if an awareness campaign gained traction. As it is, I will take the additional risk to avoid looking dumb.
I personally believe that (personal adult) helmet laws are a violation of individual liberties but we should create laws that force bike/scooter sharing companies to make sanitary helmets available. It is better to regulate business behavior than personal behavior.
Helmets are also insufficient on bikes but they significantly reduce injuries. With cars I'm not quite sure what problem you would be trying to solve because they probably wouldn't actually appreciably reduce injuries (I don't many of those car deaths are just really simple trauma to the top of the head that a helmet would actually protect against)
Oh come now, top of the head? Full face helmets are the better option, and if we're really looking to be safe, we should require them, and anti-whiplash headrest connections, as well.
Similarly six-point restraints, I'm always confused why there's just a lap-and-shoulder belt in most cars.