The Low-Tech AI of Elden Ring

This is behaviour trees. What you’re describing is behaviour trees. Edit: I see later you say it isn’t a behaviour tree but this is how a lot of BTs are implemented. They don’t always loop from the root. A lot of the time according to state the root is redefined off of a branch and that sub tree is looped until going further down the tree or even into a different tree. Much like the stack you are describing.

Perhaps this explains why Fromsoft npc quests are easily the most inscrutable in all of gaming. Like, okay Hyetta, have another “grape”, aka eyeball, oh now you’ve moved to the bridge in Liurnia, cool. I’ve exhausted your dialogue but you’re stuck. Oh I have to reload the area and exhaust it again to advance your quest. Okay, cool. Now you’re in a random church and you want a “fingerprint grape”. What?

It’s all part of the Fromsoft experience but man, who writes these things?

As a game dev, the fact "AI" as a keyword became totally unusable is quite annoying.

Low tech AI? Its sounds like standard game AI. I would really like to hear what the author would deem high tech game AI.