If you assume Level 5 autonomy exists, you don't really need ANY control surface inside the car. Those just become useless artifacts. Steering wheels, gear shifters, gas/brake pedals, turn-signals, or rear-view mirrors.
Really, even map apps. Those just convert to glorified ToDo apps, where you say where you need to be at what time and the AV figures out how to get you there. Showing your position on a map is just more of a curiosity, like the airplane in-flight scenes, giving you a rough sense of place and calmly reassuring you that you are on your way (instead of, say, plunging into the sea).
You don't really need car windows either. Could be replaced with screens that show idealized imagescapes to enhance the transportation experience, or a movie.
Not requiring brake pedals is just the first logical step, if you want to let a machine drive you.
For those who actually enjoy the driving experience, AVs are stupid wastes of effort and tech.