Germany's Mittelstand has leaders in many niches, but, as I discovered, those niches tend to pay SW devs less than CRUD or mobile app devs earn in SW focused companies, since the market of those niches is already old and saturated so the economics are similar to that of a zero sum game with minimal space for growth.
Well, that’s not something OP can easily change. But as someone working in Germany I’d say unless it’s literally a string of jobs you stayed in for less than a year each it’s not an issue- it is quite normal in software to switch jobs every 2-4 years.