The thing is, in the real world, you cannot rule out that there are cars that don't have the required hw or sw on the road. Maybe in some future there will be n

The thing is, in the real world, you cannot rule out that there are cars that don't have the required hw or sw on the road. Maybe in some future there will be no such exceptions, but the driverless cars technology is not going to wait for that. For the foreseeable future, the solution must be a hybrid (human/old tech/new tech) , unfortunately.