(Spoiler here; I’m dropping the tag so that the whole discussion doesn’t turn into a grey wall.)
What do you think aged about this one? It is hard (I needed a hint, back in the day) but it’s not based in any convention that has disappeared from modern IF. Rather the opposite. It’s thinking about the game-world as a real place (i.e., the thief is a dextrous and inquisitive character) rather than a system of verbs and nouns.
The Cyclops ODYSSEUS solution is kind of worn out, in that it requires (a) knowing a particular bit of literature and (b) thinking that it will function as a magic word. (The book doesn’t actually make this any better.)
However, the alternate solution – the lunch – is pretty well clued as a thing to try. Even if the outcome is surprising.
Zork isn’t a very cruel game
In IF discussion, “cruel” is often used in a specific jargon sense. Zork is 100% “cruel” in that technical sense: there are many ways to get into a walking-dead state without knowing it. (See this thread.)
In the colloquial sense… you’re probably right, although it’s hard to compare the wild patchwork inconsistency of Zork (and Colossal Cave) with the more coherent story worlds that Infocom was producing just a couple of years later.