Well, he said "computers" not "computation", but I can see how stating the former necessarily begets the latter. I want to back him up in some ways, but to also narrow the scope of his statement to not include all computers:

The presence of a separate, non-computational storage in computers based on the von Neumann architecture implies the representation of state (at some level or another) is possible by those same machines. Consequently, we are tempted to utilize that capacity for state as storage for intermediate data within program execution itself, rather than just as a place to store the executed program itself.

I could be totally missing the mark on it having to do with the von Neumann model of storing, fetching and executing programs. But from my limited reading about computers such as ENIAC, which required the circuit to be altered to route signals prior to execution, and then run through the program all at once. Someone please correct me if I'm wrong, because this stuff fascinates me and I'd love to be told straight.

TL;DR: Storage implies state, so we wrote tools (languages) to leverage that.