As road safety is a win for the whole of society and not only the driver it would make sense to incentivize safety at the government level. On the other hand there are already incentives in the form of insurance, which is mandatory at least in most (all?) places and should take into account vehicle safety. If autonomous vehicles are safer insurance premiums should go down for them, as it happens for example for vehicles with smaller power trains.
I'm not really sure about the power train, if it's still relevant.
Vehicle value impacts the premium, since the policy may cover things like theft and vehicle damages. However the biggest risk is damages against persons. Truck insurance for example is very expensive not because the value of the truck but because an accident is more likely to involve deaths and permanent damages. It's not unusual accidents for several million €. That said there are lot of considerations for selling policies. The insurer may make a discount for a risky sports car if it thinks it will recover the cost cross selling you other products. Or for commercial pressure, accidents are a problem for the future. But yes, you are right, it's not a certainty.
