The article gets some other major details wrong, like:

> Zork is not a PDP-10 executable, it’s actually a virtual machine executable, which is in turn run by an interpreter written for the PDP-10.

This summary confuses two or three different generations of Zork -- the original MDL and Fortran versions written at MIT (which did indeed run on the PDP-10) and the later ZIL reimplementation by Infocom (which used the Z-machine VM and was targeted at microcomputers). As far as I'm aware, there was never an interpreter for the PDP-10, only the -11, and even then only for internal use.