I have received excellent service in many a post office but I have also received very poor service from just as many if not more of them. One postal employee used to assist the older customers by repackaging their stuff up for free (using their own tape and boxes)and another would help people write all the addresses on those annoying little sheets of paper you have to use to get anything done.
Then we would get those that would tell you to fix or re-write an address or relabel a package or overcharge for postage and close the door to the back-room never to return.
The primary responsibility of the USPS is not the timely delivery of printed communications and packages, it’s to manage the benefits of their employees and union retirees.
We have a PO box at a rural post office. We get great service from the one guy who works there. If we didn’t, he’d probably find his house getting burned down.