That's not how AI will take over Hollywood. Most likely, it will be hybrid work, when good but broke actors will sign contracts that allow studios train and use their AI avatars in future movies and promotional materials.
We know this because the studios have already tried to do this and even Z-list actors expect 6-figure payments for the loss of control of their own image in perpetuity.
Why do people watch movies? Theres a whole lot more going on than just someones image.
I guess studios won't even need to do that, they will crank different versions of movies and A/B test them until perfection, with completely artificial characters, for different audiences.