> Physical buttons make this impossible. For many years now we've had various interfaces that use physical buttons whose function can change at different times

> Physical buttons make this impossible. For many years now we've had various interfaces that use physical buttons whose function can change at different times during operation, the current function being indicated by the screen: Old fashioned ATMs with 4 buttons on each side of the screen, many business-class feature-phones had "soft-keys", even old DOS programs that used Function Keys are conceptually similar. There are differing degrees of compromise vs utility.