I'm thinking there might be some touch-sensitive areas of the steering wheel to change display configurations, activate turn signals, radio volume/audio tuning. They might not be physical buttons in the traditional sense, but like trackpads for your thumbs. They might even have flexible OLED displays that change depend on your settings. They'd have to be made pretty robust to withstand repeated use over 10-15 years.
So basically, as you approach, or you get seated in the car, the trackpad areas on the steering wheel will illuminate with the default settings. I imagine some functions will be fixed (i.e. turn signals) but others will be configurable. However, if it's intuitive enough, maybe backlighting the trackpads themselves with OLEDs would be unnecessary. The functions would be displayed on a virtual steering wheel on the display. I don't know...Just having a stream-of-consciousness monologue here.