@aetios in germany you could theoretically also get the Information right now as well. You would just to put more effort into that instead of having an oh-so convinient list of that. Though tbh if the nazis come to power they would have all that info that their disposal anyway.
Working for the government I can tell you it is quite easy to get ahold of information once you are there. Like we keep a history of resident registrations. pretty sure you could also deduce a name change plus change of honorific (? can't find it basically if Anrede is "Herr", "Frau" or nothing).
It just would be more work and likely illegal in the SBGG