It can definitely plan such things. Because agentic systems don't have to output a book all at once. The mainstream still lives 1-2 years in the past.

Agents can plan out a narrative draft, write it out section by section, maybe out of order, then tweak it, plant clues if it wants to, then trigger it in another chapter file etc. Then read the whole thing, reconsider, etc. It can iterate. I'm not saying it will be great literature, but the problem isn't the inability to create long range references.

My bigger point would be this: arguing from such mistaken technical ideas, when not having any idea about the tools is a sign that people's real problem is none of those technical limitations, but Western culture has lost the vocabulary to express their true sentiment. They are grasping for words but can't reach for "soul" and other religious terms because that would sound ridiculous in a secular modern world. But they clearly want to express that and we'd be ahead if we could discuss in such actual terms. Would you want the machine to write literature if, hypothetically it could write indistinguishably from any great writer? I guess not. Because there is something mysterious and important about the human spirit. (the same vocabulary-inaccessibility is plaguing other culture war issues too). People will rather talk about fake water consumption problems than touch the topic of the human soul or spirit.