There won't be an OS anymore. All you need will be a network enabled graphics driver (Hello X11) for the AI to connect to and draw on.

Then the AI will just create the image that resembles a spreadsheet or whatever on the fly and write straight to the framebuffer.

All other tasks that go with the spreadsheet will also be done on the fly.

But I could imagine our language will change and certain words will basically act like macros and create a set of assumptions and specifications for the prompt that you're using.