There is a significant regression in Xcode 16.0 and 16.1 (16B5014f) in that it no longer allows asset files other than .SCN files to be added to a .scnasset group and folder. This really wrecks our ability to maintain our app since we heavily depend on additional assets like .USDZ, .JPEG, .PNG, etc. files to be able to be included in the group for on-demand resource tagging and loading.
I filed FB15239224 but I'm wondering if this is intentional and if anyone knows of a workaround.