That just blew my mind. I've never thought of a computer as _being_ all of those devices. I've always held the mental model of a computer being a really dumb robot of sorts that would perform separate actions.
Like a computer could _do_ all of those things, much in the same way I can drive, cook, balance a checkbook, etc.
Knowing that a particular interface is almost completely accidental is often the key missing piece in going from being utterly helpless to solve a problem to being able to puzzle it out.
Yes! A lot of interfaces are largely arbitrary fictions! If more people understood this, there would also be fewer fan boyish arguments.
Also suggests a metric/strategy: minimize the amount of fiction in your UI and maximize the fundamental principles. (Example, sliders are well understood, because most people understand basic geometry.)
Only a matter of time before some biotech genius invents a fruit that has different tastes depending on how you peel it, then it's my turn for a brain meltdown.