I found myself blocked from doing anything interesting with Apple’s Reality Composer tool due to the lack of readily available USDZ-format files. My kingdom for a Lego minifig!
Therefore it’s cool to see that they’ve released a simple utility meant to facilitate conversion:
The new Reality Converter app makes it easy to convert, view, and customize USDZ 3D objects on Mac. Simply drag-and-drop common 3D file formats, such as .obj, .gltf and .usd, to view the converted USDZ result, customize material properties with your own textures, and edit file metadata. You can even preview your USDZ object under a variety of lighting and environment conditions with built-in IBL options.