> There is an inferred "Speaking as a German", so the author is a letting me know they're German.
Yes, there is the "speaking" part inferred, but the grammar still does not
work like that. As a supposedly educated English native speaker, you should
know better.
If I said: "As an idiot, you're wrong", I could not possibly claim that
I called me an idiot. Why suddenly the subject would change in the very
same sentence structure?