A key problem in Germany is that the job-market is underpaid compared to the US, Switzerland, Luxembourg etc.
Nowadays, the majority of researchers works on AI-related challenges that are industrially motivated. Many of these researchers do not desire to stay in Academia.
This makes it even more important to have a job market that matches the qualifications of these researchers upon their PhD-level education. I don’t know if Germany will be able to incentivize people enough.