No, crashes in the US happen because Americans are shit drivers. They are shit drivers because you get a free driving license with box of cereal. Germany on the other hand has one of the strictest driving tests there is. A German with a driving license has had many hours of instruction from a professional instructor.

In addition, American cars are shit. Lots of poorly maintained and unsafe vehicles on the road with very lax regulation. By contrast, German cars have to pass a very comprehensive yearly safety inspection.

83 million Germans, 63% above 16

Not sure why you think this is relevant. Children aren’t allowed to drive in Germany.

How is it a retcon? The use of giga- as a prefix for 10⁹ has been in use as part of the metric system since 1960. I don’t think anyone in the fledgeling computer industry was talking about giga- or mega- anything at that time. The use of mega- as a prefix for 10⁶ has been in use since 1873, over 60 years before Claude Shannon even came up with the concept of a digital computer.

if anything, the use of mega- and giga- to mean 1024 is a retcon over previous usage.