He was open to doing at least a few years over there; he’d enjoyed his exchange during university back in the 90s.
I was the one who said no, having seen the hell my colleagues married to Germans and other western Europeans were going through with US immigration.
Instead, I got a German residence permit without much fuss, and converted to a permanent one (Green Card equivalent) at a renewal when the clerk pointed out I was past the minimum time needed on my renewable one and encouraged me to apply.
Everyone complains about German bureaucracy, and I did have to bring in a fair bit of paperwork, but they do a prep appointment where they give you a list of exactly what they want to see from you specifically when you file your application.