Most computational systems in cars have been reactive in nature, not predictive. Driving is a predictive act (you see a fork in the road ahead, you know which way you will be turning and you know how you will operate the vehicle's controls for that turn. Even if the vehicle is very sophisticated and can see the curves ahead, it still has no way to know which direction you will turn so it cannot prepare itself for what you are about to do)

As long as a human is in control of the vehicle, the vehicle's systems must necessarily be reactive to the driver's input - or else they will annoy the shit out of every driver they incorrectly interpret.

Driving as a utility might be as simple as getting a human from home to work and back, but if that's all you need to accomplish there is no reason to have a "nice" car. 100% of us should either ride buses, bikes, trains or have white, bland egg shaped vessels with just enough power to get down the road efficiently. But many of us drive because we enjoy it - the force amplification is intoxicating and certain kinds of personal involvement become part of the ritual. Even in cases where a conventional, reactive automatic transmission is objectively superior in every way (off-pavement driving on severe terrain) a lot of people still prefer the inferior manual way of shifting gears just as a matter of personal preference.

As a general rule, manually operated systems allow the human operator to "break the rules" and do things that seem hazardous or unnecessary to the programmers responsible for automation - but the human in control of that system in the moment will have access to sensory input and intuition that cannot have been predicted in the development stages of that system. A human has learning and experimentation capabilities that still have not been matched by machines and in the analog, organic world there are still situations which a machine cannot accommodate. Retaining human control in those situations gives a greater array of options.