I really hope USD is not it. Having worked with it trying to build stuff for the vision pro, it's a massive software library pretending to be a file format. It is inexorably linked to the source code that processes it to the point that making a processor for the format is a non-starter, and that seems to be by design.

The codebase is dense, hard to compile, using outdated dependencies, and doesn't play nice with anything else. Documentation is sparse, often incorrect, and severely lacking in anything like a new user guide. Everything assumes you work for Pixar already and know the ins and outs of their pipeline.