When our cars were built they (and Volvo's) were the safest cars in the world, by a rather large margin. Mercedes was among the first to build cars with a monocoque structure, rather body on frame. They engineered crush zones to absorb energy in impacts, reducing the impact of that energy on the occupants of the car. Those passengers were protected in a safety cell or safety cage that was part of the structure of the chassis. This was developed by Mercedes in 1951 and is used today by every car maker. (There is some argument here, as SAAB, had introduced a safety cage in the production 92, which began to roll off the line in December of 1949--it was the first SAAB car made). Mercedes, made huge padded steering wheels, so if you did impact the wheel the damage would be minimized. The 3-point seat belt (invented by an engineer at Volvo) minimizes movement front and to the side in various impacts. The steel sunroof didn't shatter glass on the occupants, the roof structure was reinforced to support 10 times the weight of the car. Door latches and handles were designed and reinforced to doors could be opened easier, those door handles were designed for leverage so emergency responders could just pull on the handle, rather than have a flimsy flap to lift up on but no leverage to pull. Mercedes has over 80,0000 safety patents a lot of them predate our cars.

Mercedes was the first to put airbags as standard equipment in cars, (GM has been offering optional airbags in some large cars since 1974) and seat-belt pretensioners with the 1981 S-Class, beating the US government mandate for passive restraint systems. Mercedes called it "supplemental restraint systems" (SRS) because they were philosophically opposed to the idea that passive restraints should ever be considered adequate to the active restraint of a seat belt. The US safety regulators had this misconceived notion, where they'd given up on getting people to wear seat belts and mandated technologies to protect the stupid unbelted occupant. And that was the mandate, create a passive restraint system. Some car makers used motorized seat belts for the shoulder strap, but the lap belt still have to be manually belted. These were stop gap measures allowed by the DOT to give time to carmakers to design and engineer airbags.

Are cars safer today? Yes, for sure they are, with many technologies that improve both active and passive safety. But, to be honest the only real safety technologies I wish my W123 had would maybe be seat belt pre-tensioners and ABS (which I can minimize the need of by being alert, keeping a safe distance, and driving based on surface conditions).

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1983 W123 300TD US spec Turbo engine, with Euro bumpers and manual climate control, and manual transmission.