Denmark had a universal postal service for 400 years until the end of 2023, but as digital mail services have taken hold, the use of letters has fallen dramatically.
Public services send communications via a Digital Post app or other platforms and PostNord Denmark says the letter market is no longer profitable.
Germany will be safe from this for decades to come. Though I am interested in how exactly this Danish digital mail works, I assume it's not just email (i.e. extremely insecure).
We have a national electronic id which is pretty much only used for official (logging in to taxes, signing contracts) or semi-official (logging in to your bank, pension and other big services) stuff. You use this to log in to one of a few "official mail" providers (same use cases). So your identity is confirmed and so is that of the sender.
You usually get an email when you get this kind of mail. Then you need to log in using 2 factor authentication.