While I think you are right that the von Neuman architecture was not an arbitrary choice. But I think big computers are evolving into something else. In theor

While I think you are right that the von Neuman architecture was not an arbitrary choice. But I think big computers are evolving into something else. In theory, a von Neuman machine asks for a word of data and gets it back from RAM. But nowadays we need caches which communicate with the real RAM using something vaguely like network packets. The hardware then emulates a von Neuman addressing scheme on top of that. But look at what software does with all that RAM: good programming isolates objects from each other and forces them to communicate through well defined interfaces. Bitter experience with threads teaches us to pass values around more than to share state. It seems there is a room for the software abstractions to map more directly onto the hardware than they do now. In which case computers will no longer be giant von Neuman machines, but networks of little ones.