> Governikus provides the online service for authenticating your OpenPGP key on behalf of the German Federal Office for Information Security (BSI). This online service compares the name read from your ID card, your electronic residence permit or eID card for citizens of the European Union with the name specified in your OpenPGP key. If the names match, your public key is electronically signed by Governikus, confirming the match. The Governikus public key can be used to verify the Governikus electronic signature.
So this is apparently useful if somebody wants to send an encrypted email to somebody else and want to ensure that only the desired person can read the email. For that the sender would have to check that the OpenPGP key got signed with the Governikus public key before encrypting and sending the message.
What that doesn't seem to address are multiple people with the same name. So the sender know he's sending an email only John Doe can read, but he still don't know which John Doe it is.
To me that sounds like something which makes only sense for a few limited use cases.