It's in addition to the existing security.

My username doesn't fit in the web form. Instead of seeing "Symbiote" (which can be read and remembered immediately) someone sees "Sym-065c7d6c-e0b3-4d——" with half of the random characters not visible.

People in Denmark are expected to use this system to authenticate money transfers and to digitally sign documents (e.g. buy a house!).

My investment account allows up to 5,000,000DKK (€670,000) to be transferred with this digital signature.