So how is buyers ID going to help with Amazon not inspecting returns? Amazon doesnt even mark returns in any way so they dont know where it came from and where it ended up. Hell, they dont even mark/track source of co-mingled inventory!
And crucially - Amazon doesnt do this tracking on purpose so they can have plausible deniability while screwing merchants.
It doesn't help with inspecting returns. It simply adds another hurdle that has resulted in a slightly smaller percent of fewer returns, saving them a significant amount of $$ at scale.
Btw, if Amazon is a fault, where they can't shift the loss onto a seller or third-party, the delays will go on for weeks, if not forever. You have to do a chargeback.
And crucially - Amazon doesnt do this tracking on purpose so they can have plausible deniability while screwing merchants.