By all accounts they are.
By whose accounts? Trust me, they are not making money on Amazon. How could they? They offer cheaper shipping than the market demands and they pay massive amounts of overtime to deliver Amazon packages. Is the USPS operating in the black? No. The amount of overtime alone offsets any revenue generated by Amazon. Only the USPS was stupid enough to make that deal. FedEx and UPS didn’t do it. In fact, the USPS delivers a large percentage of packages originating with Fedex and UPS “the last mile”. Why? Because those two companies save money “allowing” the USPS to do it.