Starting in the early 90s, Germany invited Jews from the Soviet Union to settle in Germany, but their ancestry was not considered German. Germany did not strip them of their citizenship during the Third Reich, so that type of right-of-return law did not apply, either. Some would have been hesitant to accept citizenship any way. (This was the time when refugee homes were burning in Germany, and the unconditional right to political asylum was abolished.) The effect at the time was hat professional qualifications weren't recognized, which meant that many did not have access to high-paying jobs. Previous pension contributions or equivalent in the CIS states are not recognized, either. The end effect today is that many among the older generation are dependent on non-pension welfare payments because the German state pension they receive is so low. This makes it impossible for them to obtain citizenship because of the self-sufficiency requirement.

Other persons whose ancestors emigrated from the Holy Roman Empire (long before Germany existed as a modern nation state) are considered Germans by blood, so it's not about the time of emigration from Germany. These decisions are arbitrary, and it's puzzling why Ashkenazi Jews are still not treated as having German ancestry.