GPU renderers exist but they have pretty hard scaling limits, so the highest end productions still use CPU renderers almost exclusively.

The 3D you see in things like commercials is usually done on a GPU though because at their smaller scale it's much faster.

I'm not sure how well suited GPUs are to the workload. They're also rather memory constrained. The Moana dataset is from 2016 so it's not exactly cutting edge but good luck loading it into vram.

https://www.disneyanimation.com/data-sets/?drawer=/resources...

https://datasets.disneyanimation.com/moanaislandscene/island...

> When everything is fully instantiated the scene contains more than 15 billion primitives.

There's plenty of GPU renderers but they face the same challenge as large language models: GPU memory is much more expensive and limited that CPU memory.

A friend recently told me about a complex scene (I think it was a Marvel or Star Wars flick) where they had so much going on in the scene with smoke, fire, and other special effects that they had to wait for a specialized server with 2TB of RAM to be assembled. They only had one such machine so by the time the rest of the movie was done rendering, that one scene still had a month to go.