I agree with you, and just a few more observations about where do I think the current bottleneck might be: I wonder how well the model handles with re-using objects/people/scenes. Like, can I create a character and then use him again along 10 different shots? Also, I'm pretty curious about how the user interface looks like. Cause they the text-to-video model interfaces seem pretty limited compared to the freedom a person has using Unreal Engine or Blender or shooting a movie in real life.
How would the golden standard text-to-video user interface would look? And I have been thinking on this for years, even before the current generative AI boom, and I wonder if it could generate like a 3D representation of the scene that you described, like there would be a file where you could very easily change things around, as if that thing had been created on Blender or whatever, but very very user-friendly and easy to edit things.
It will seem silly what I'm going to say, but the ideal interface, it reminds those movies people did using the game "The Sims", and how you could very easily move objects, and move the camera, and so on. What I'm trying to say here is that I would imagine these models creating a 3D representation of the scene, and the movie-making process ends up being somewhat similar to how could you could customize objects/people in that game.