Germany has
WAY more difficult driving licensing standards than the US.
My high school English teacher father used to ironically remark about how students who failed his class repeatedly (often for all four years) somehow always managed to pass the drivers license test. Funny that.
Your calculation also neglects the cost of auto accidents in terms of wasted life. There will be an accident on I-5 between San Diego and Los Angeles every single day--generally multiple. When that happens, an enormous number of people wind up sitting in their cars for an extended period of time. That accident may not have actively killed someone, but it caused many thousands of people to waste an hour+ of their life. If a thousand people waste an hour every day, that's one "dead" year of human life every 9 days. And that multiplies across the entire city and then across every city. The cost of automotive fender benders and the time they waste exceeds the "death toll" of driving by quite a lot.
Humans suck at driving. It's a boring, repetitive task with sudden moments of sheer terror. As long as everything goes "normally", it's okay. When something unusual happens when driving, most outcomes are random. The lack of deaths and injuries due to driving is more due to automotive, traffic and safety engineering than it is due to active crisis decision making by human drivers.