It really is manufacturer by manufacturer and product by product
RB-WAV-1385: Doesn’t seem to have a CAD / STEP file available RB-PIT-123: Doesn’t seem to have a CAD / STEP file available (though they provide global dimensions below)
Usually CAD files are not open source.I see that manufacturers often make the PCB layout open source but the CAD files are nowhere available most of the time.
Just to add our two cents, though it doesn’t particularly help you with the two products you listed but maybe with a future project … as the accepted answer already had mentioned, this is a matter often decided by the manufacturer.
We provide 3D models (most of them in *.step) for all of our products. All are available on our PTSolns Documentation Repository: https://docs.ptsolns.com