You were lucky. What would have you done if you couldn't prove you no longer had possession of the car? If they had ticketed the driver directly, none of that could have happened to you. There would have been nothing for you to prove.This is why the state I live in has had that law requiring ticketing the actual driver and not the car decades before traffic cameras were even a thing.

And since there are no self driving cars that can be commonly found on the roads today, that's a silly idea. And IF that time ever comes, someone is still going to need to be liable for that self driving car as it goes down the road. That software is going to be so locked down it must follow all laws without exception. Because the company will hold the liability.