Believe it or not, but there’s a lot more that goes into filmmaking beyond the premise.
Parasite, The Substance, Uncut Gems, mother!, Krisha, Tangerine, and The Lighthouse are some movies from the last decade that are novel in ways beyond their premises.
No generic prompts to an LLM could create those movies, even if it could spit out a vague 2 sentence premise that matches them.
Note that I’m not saying it could never happen, but LLMs as we have them in 2024 produce regurgitated slop, and require significant creative input from the prompter to make anything artistically interesting.