I think it is because there is also a lot of value of just assisting the driver. It is much more comfortable to drive if the car itself keeps the same speed as

I think it is because there is also a lot of value of just assisting the driver. It is much more comfortable to drive if the car itself keeps the same speed as the car in front of me and follows the road. I also feel a lot safer if my car would automatically brake if I'm distracted and a kid runs out in front of the car.