AI's gonna need a competent developmental editor, and to be applied incrementally with human decisions and input in between, for at least a while longer (we'll see if it keeps progressing past that—seems likely, but one never knows)
[EDIT] To be clear, it won't need those things to produce a story at all, but AI-assisted stories that have had significant human input applied will be notably better than wholly-AI ones (the kind of on-demand storytelling you're alluding to) for some time yet.
[EDIT] To be clear, it won't need those things to produce a story at all, but AI-assisted stories that have had significant human input applied will be notably better than wholly-AI ones (the kind of on-demand storytelling you're alluding to) for some time yet.