Earlier quoted context omitted.
Actually the Zorks weren't deterministic, especially Zork II. The Wizard could F you over pretty badly if he appeared at an inopportune time.
I feel like you are being pedantic. There are very few parts of Zork that are not static to the game. Yes the thief shows up randomly but that’s not the main point of the game.
Can't recall anything like that in Zork 3. (Edit: apparently you could get shot randomly when using the time machine in the Royal Museum.)