I'm sorry but this is just wrong. Cars are very much digital for years now. Everything is connected together using CAN bus and handled by a computer. This computer is completely seperate from the entertainment system, which often isn't even connected to the CAN bus.

My car is 10 years old, not expensive and almost everything is digital on it. For example the gas pedal is simply a pedal connected to a sensor and a motor. The motor allows for force feedback and automatic actuation, whilst the sensor let's the computer know what I intend to do. Depending on what mode the car is in and what it sensors are saying, it'll interpret the signal differently.

All of the parts of the car communicate digitally and without this the car wouldn't be able to run. This has been the case for decades now. If you have a fuel injected car, it needs a computer to run at all, it needs things like a lambda sensor to run properly. Things like ABS and collision detection is handled through a computer, etc.

The speed as displayed on the analog speedometer is almost certainly read by a digital sensor and communicated through the bus as a digital signal. The computer then puts that signal into the actuator to move the needle. It's not like a belt and pulley system connected to the dash. Other systems in the car need to know the speed as well, for example the variable power steering needs to know if you are parking, driving through town or on the highway. This is all done digitally.