The postal service has been shifting away from using air transport for the past several years and will continue to do so as much as possible. FedEx and the USPS went into negotiations quite a while ago. For those of you who missed it, FedEx wanted guarantees of volume that the USPS was unwilling or unable to provide. As a result FedEx wanted higher rates on the basis that the costs of flying the freight was essentially the same whether the planes were full or 2/3's full and that the lack of volume was rendering many of those flights money losers. They said they would not renew the contract if they didn't get favorable terms, just as they did with the Amazon contract.
If you think that the loss of a contract that wasn't making any money is bad, well, OK.