Sure. And my point is that the assignment is poorly conceived if an LLM's output can appear to "have ideas" that satisfy the prompt. Last I checked, they don't do a good job of modeling a specific, non-notable person within particular constraints, and then all the relevant life experiences of that person. An LLM essay should be human-detectable for the same reasons that one from an essay mill would be.

No matter how intricate and detailed an object is, it will appear similar to any other blurry mess if it's viewed through a shoddy lens.

I think your point stands for upper level work; however, at medium to lower levels, your counterfactual starts to weaken. The ideas have always been there, but it's the ability to express them--well enough to notice their presence--that is not.