Not true. Seat belts were the first great leap forward in automotive safety. But airbags were the 2nd great leap forward, and automatic emergency braking is now the 3rd great leap forward in cutting fatalities. Other technologies (pretensioners, crumple zones, lane-keeping cameras, anti-lock brakes, etc.) have all played their role as well, but those are the big three. (I was an automotive quality engineer focused on safety technologies for 25 years in my first career.)
I’ll defer to your automotive safety experience.
As a Boeing Engineer with 20 years in Experimental flight test and having had my designs certified for flight. I don’t think much of airbags. I don’t think you are allowed to ship them as cargo on aircraft. Much like lithium batteries.
Engineering is all about trade-offs.
Auto people accept more death than I did on aircraft safety decisions.
Aloha.