wars tend to be a lot shorter than the existence of cars

Yeah but depends on how you define wars. For example the mongol conquests is up there and that lasted a good 60 years. You could say thats multiple wars tied up in a single cause or crisis.

These events can be on a spectrum between the thirty years war, to the crisis of the third century and the three kingdoms period, each around 60 years, to the hundred years war. The longer it gets the more it goes from being about discrete battles in a war, to discrete conflicts in a war, to discrete wars in greater war/crisis.

Either way on the ground these crisis look the same for the common people. Armies repeatedly going back and forth over your land, looting, raping, killing and spreading disease and making your life miserable and after a few decades this becomes normalized. In this sense cars could be a good comparison, a persistent normalized threat constantly killing people.

The casualties for cars even in this context look greater. The three kingdoms period, probably the deadliest of these crisis, caused 30 million deaths. Why it doesn't compare well though is that was half the population of China, whereas 70 million is probably only a couple of percent of the people who live in car centric countries.