When people say things like that they mean it as a rough mental model.

Bit like when people say "it's like riding a bike" they're not actually talking about bicyle riding being the exact same activity.

Coming with this in response:

> f(x) -> P(y) ∪ P(z1) ∪ P(z2) ∪ ... P(zN)

is a failure in human communication not a disagreement about what LLMs are or aren't.