Fair point about USDZ and glTF. I'm thinking about this from a web developer's point of view which may skew my perspective. USDZ is unusable on the web and probably will remain that way since you need to use an SDK to read the files unless someone can work some wasm magic.

glTF is a full scene exchange format, however, I deal with glTF files on a daily basis and the overwhelming majority contain only models and animation.