That's fine if you're connecting everything to a computer, but it's kind of a step backwards from what MIDI used to be, which was an easy way to connect almost any keyboard to almost any synthesizer made in the last three and a half decades or so.

I've wondered if CAN bus would be a good modern-ish alternative to DIN-5 and USB, but I don't know enough about it to say if it has some limitation that's not immediately apparent but which would become a problem. (On the plus side, it's much faster than plain DIN-5 midi, allows longer wires than USB, and it seems to be supported natively on a lot of cheap microcontrollers.)