No one disagrees with this, as best I'm reading the conversation.
The cook is in the kitchen because of <insert in-fiction causal explanation here>.
Just the same as a wandering monster is at this junction of the dungeon because of <insert in-fiction causal explanation here>.
And just the same as, in the village that
@Maxperson told his players about, there is a farrier because of <insert in-fiction causal explanation here>.
In each of these cases, there is also a reason, in the real world, that the GM narrates the presence of the NPC/creature:
The player failed a skill roll. The wandering monster die came up "6". The player asked Maxperson, "Is there a farrier in this village?"
Pointing out that the GM has a real-world reason to narrate the NPC/creature doesn't get us very far into analysis of these examples. Asserting that there is something
unrealistic or "quantum" about the cook but not the wandering monster or the farrier is likewise not going to get us very far: in each case the GM narrates something not because
they considered the fiction and its logic impressed itself upon them but rather because
something happened at the game table that prompted them to narrate the presence of a NPC/creature.
At a minimum, it seems to me that we need to talk about participant roles (ie player vs GM). We also need to talk about
how action resolution interacts with participant roles. We also need to look at
how action resolution, which is a thing that happens in the real world,
relates to what happens in the fiction.
I don't think any of those things in isolation will enable identifying what is going on with these examples.
Just as one example: I'm 90% or more confident that
@Maxperson does not regard the question "Is there a farrier in this village?" as an action declaration. Rather, it is a prompt to the GM to do some spontaneous worldbuilding, and that is (in his view) part of the GM's job.
Whereas in Burning Wheel, "Is there a farrier in this village?"
is an action declaration, to be resolved - following further discussion, if necessary, to establish intent and task - by either a Circles or a Resources test.