My feeling is that he's suggesting more than just a discovery protocol. Once both machines are running a common protocol, even if that protocol is used to bootstrap more sophisticated protocols, I feel like we've moved beyond talking to aliens.
I don't know where to draw the line, though. Is it fair to assume both machines speak tcp? ip? I don't think Brett is suggesting computers should organically re-discover ethernet based on analog probing, but I do think he's suggesting more than just
bonjour.
My favorite take on it, which I don't think is an indented reading, is that computers need to share a common protocol with their neighbors, but not necessarily their neighbors neighbors.