Problem I see here is not even in tech. Movies' language is ridiculously controlled and intentional, up to the point you can tell who is the director or what influenced them. It comes in completely opposite direction to what LLMs are as a tool.

It's demonstrated by endless remakes\sequels not holding any water, and these done by real people yet lacking many things that made originals stand out. LLMs can help you here and there, probably, but it's not revolutionary to the industry. Even endless uninspired sitcoms can hardly be imitated with generative models. Especially with consistency.

Honestly, I'd suggest you to go ahead and try it yourself. Even a campy movie for friends and family or a simple musical clip requires a lot of effort. And even if you have all scenes at hand (by generating them?), editing can take days and decide if it's good or a flop. That's why some directors only work with familiar editors who they can trust with their movie. And there are many professions like that in the industry. You lose nothing and would probably get a fun hobby.

One thing: you can use your phone, but set focus to locking once you hit the rec button. Camera changing focus is the most annoying shit that can kill a good shot.