I feel like there's very little engineering reasons why we can't...
It's not an engineering problem. One could cut new holes in the front bumper of an old car, add forward-facing radar, tack on a display and a computer to drive it all, et voila! Now you have collision avoidance! Except even in volume, you've probably spent more than the car is worth (labor will be the killer, not hardware), or enough that the person whose economics dictate an older car can't afford the upgrade.
Lane keeping? I don't even want to think about what that retrofit would involve.
It's not an engineering problem. One could cut new holes in the front bumper of an old car, add forward-facing radar, tack on a display and a computer to drive it all, et voila! Now you have collision avoidance! Except even in volume, you've probably spent more than the car is worth (labor will be the killer, not hardware), or enough that the person whose economics dictate an older car can't afford the upgrade.
Lane keeping? I don't even want to think about what that retrofit would involve.