@vertigo @akkartik @seanl @h Electronic circuit diagrams are another interesting counterexample. They evolved before computers, of course, so there wasn't a need for them to be easily serialisable across a planetary information network originally designed to host 5-bit Teletypes.
It would be *super cool* to have graphical languages - I've expected it since the Commodore PET's graphics symbols in PETSCI. But interop is the big problem. Things like PETSCI just died, and so much was lost.