There are hardly any big research org working on training AI to learn how movies work, even though we have enough data resource to train, we have huge liberary of movies with scripts as prompt, since every frame of a movie is to be analysed and broken down to details, it will be a huge workload for training, much bigger than what Big data companies compute today,

TO ANSWER THE QUESTION -

We can possibly see a incomplete version of AI short movie generation that looks realistic In 2025-2027 it will take few more years to perfect the fine creation

Last remarks , as you know even with stable diffusion the video that are created are not constant with character and placement, so yeah we have long way to go, rightful constant image generation will be a major pillar for such projects

Edit : dont forget about how charactar generations with behavioral charactarstics and distinct sound of charactars are important,