whoa, I just imagined a world where USPS, Deutche Post, etc - offer domains, servers, cloud services - as a natural extension of treir previous roles..
That used to be the case before the privatization in the 90s. What do you think the Deutsche Telekom is?
Some countries have digital mail services that are actually better than email because they include identify verification features
e.g. https://www.digipost.no/