Another thing that would avoid fatal crashes is reducing the number of cars on the roads, making them smaller and making them slower. That's a lot cheaper than making them more complex.
Germany also solves that problem by having no speed limit when it gets boring. Making driving engaging is the best way to create mindful drivers.
If people had to drive 2 hours at 30km/h, they'd be more inclined to quit driving. It's a stupid addiction which is way more lethal than smoking. Better public transport is a much better idea than messing around trying to improve driving. The situation where the majority of the population has (or "needs") a car is ridiculous.