I, for one, think it's a good thing that people are entitled to their mail regardless of the profitability of their mail route. That's the point of a public service.
USPS is not a business, and it’s a fundamental mistake to pretend it is, solely for the sake of slandering it.
Among other core competencies, USPS has nationwide daily coverage of the entire United States and centuries(?) of experience interoperating the the respective mail services of every country in the world and then some.
Amazon wont even take MY package one town over.
That said, the service provided by the USPS nowadays is primarily delivery of paper waste into a receptacle I am obligated to empty because very occasionally they also use the same box for packages.