As a native speaker my experience isn't that you require near native skills, I've worked with plenty of expats/immigrants who speak 'just' good German, but I'd rather increase language learning opportunities if necessary mandatory rather than lower standards.

This is still a country, not a back office for multinationals, people who talk to a German business should be able to have a conversation in German. This can be expected from immigrants. I've lived abroad myself and made sure I was proficient enough to be able to integrate. It's culturally vital as well.