Being a German I actually would not use a system like this. I don't need the government to provide identity verification to third parties in an automated way. I actually don't want the government to have any data on me regarding what third parties I use.
It is enough that I need to tell the German "Verfassungsschutz" all my social media networks, all my domains, all times that I was in a foreign country for an extended stay just because I work for an agency that does projects for governmental institutions. Not that it matters, as I had to do a similar strip tease when I started my university job as a student helping the professor.
Not that I have anything to hide, but I just don't see the government having a track record of safe systems. Or keeping adversarial actordout of such systems. Additionally these systems might only be an election gone south away from falling into untrustworthy hands with me not being able to delete the collected data.
I might currently be living in a relativ (pseudo-)democracy. But if history tought us anything, that is nothing to be forever certain about.
And it might be tech that is >10 old. But I believe you will be hard pressed to find a significant amount of people in Germany (especially in tech) that would want to use it. Maybe the fact that nearly nobody is using it tells a lot about if this is an idea worth pursuing.