Oh, yeh, don't get me wrong. I meant impossibly expensive to drop into a mid range car with no scaling up from a higher value lower volume product range first.
To each their own, but it's possible having sensor bumps on your car become a status symbol that indicates you can afford a private driver.
> not sure you can have it on a convertible etc.
Radically different car shapes are possible when human driving never happens or is very rare. Maybe a small van (like a private lounge on wheels, or a train observation car) with a huge panoramic sunroof becomes en vogue.