Beyond Zork’s map drawing code will also produce an ASCII art variant of the map for systems that can’t easily handle the custom font, like, IIRC, the Apple II.

The Infocom dev machine was a DECSystem 20 (PDP-10 architecture) until circa 1988, when they ported tools to the 68020-based Mac II.

I expect they thought the Unix source would be a good basis for future non-Unix development; comments in the source itself allude to this possibility; I’m just wondering if it was used in any shipping product. I suspect it wasn’t.