Scenes like Moana are not intended to be handled as a whole, they are assembled from little pieces - semantically independent and assignable to different people with different skill sets. It's not the matter of software performance, it's the matter of process organization.
But again: the DCC doesn't see the high detailed version of that geometry in a proper pipeline. It only sees a proxy. See my detailed reply above.
Only the renderer does see the final geometry and even that may be generated procedurally, on demand. I.e. stuff like fur, particles or the like is often generated on the fly since caching (and then reading) this data is not only impractical but also may be slower.
Think a terabyte of fur data for a horde of fluffy monsters on screen (per frame, of which there are 24 per second of film at least) that needs to be distributed to each blade on a render farm or, worse, machines in the cloud (again and again since each frame goes through many revisions in lighting/rendering before its final).
Computing the fur from a few hundred thousand 'guide hairs' on each character, on the fly, is a better approach.
I was seriously considering rewriting the Blender OBJ importer myself. Ultimately, I ended up writing an OBJ to Alembic converter, since Blender handled those more efficiently.