There was research some years ago in Sweden that cars with 4WD get into accidents 20% - 30% more often than cars with 2WD. And cars with 4WD averaged 10% higher speed at the moment of the crash.

The cause was found to be drivers with 2WD losing a little traction early in their drove and subsequently slowing down, while drivers with 4WD just kept driving like normal until they were suddenly off the road.

Another statistic is that intoxicated or otherwise impaired drivers cause more than half of all fatalities. So making a solution with machine learning and cameras that could retrofit into any existing car and just deny starting the car for such drivers, and having insurance companies cut premiums for having such gadgets installed, would be much more effective than any form of self driving or similar.

https://mb.cision.com/wpyfs/00/00/00/00/00/3E/5A/A2/wkr0011....