They shouldn't be because even as a cautious driver you are subjected to noncautious drivers and, more importantly, no matter how cautious you are a well designed AI is almost certainly better.
Both cautious & rash drivers face the same external factors, but latter are more likely to wreck themselves, sometimes without involving others. So probability of an accident for latter are higher.
AI may be good at reducing the average number of accidents, but when a tricky situation occurs, the probability of accident could be in this order "rash > AI > cautious".
To be honest, i had the same assumptions on cautions and rash drivers. But then i learned to know my new boss- he drives ralley-race cars- and to be honest, i feel much safer in such a ralley car taking to its physical limits by someone who knows the car- then in the car of a cautious driver, who is just cautious because he/she is aware of how little they know/controll the actual physical event of driving a car.
I know such a thing is nont quantifiable thus, the laws min(ability) applies, none the less, one should not judge from appearance here, but rather from actual incidence lists.
AI may be good at reducing the average number of accidents, but when a tricky situation occurs, the probability of accident could be in this order "rash > AI > cautious".