You are right in saying that all studios who can work for less money will do. That is the scary part for thousands of people working in animation and film.

Tech people doesn’t know about art, well I’m not sure, but that is irrelevant as AI are trained on existing top of the line art made by the best artistis in the world.

On the renderman subject, that is not correct. Renderman is a render engine for 3d softwares. AI doesn’t need a render engine at all as it produces images by itself. And for movies like topgun a number of different engines are used, renderman, vray, Arnold, redshift, unreal, etc.