As mentioned in one of my other comments: Yes, the Holocaust targeted other groups than Jews (Slavs, Romani, Gays, etc.). However, in learning about the Holocaust, there is usually a strong focus on Jews. In short, most people learn a lot about how Jews were targeted, and a lot of memorials and media focus on Jewish prosecution by the nazis.

At the same time, Russia has been built up as an adversary since the beginning of the Cold War, and committed plenty of their own atrocities before, during, and after WWII. The same cannot be said about Romani, Gays, Jews, or other groups targeted during the Holocaust.

With all this in mind, it's not very hard to understand why "Holocaust guilt" is centered on Jews more than other groups, and why Russians are largely exempt from the feeling altogether. I'm not saying that's fair or right, I'm saying it's very understandable.

On the other hand: I really don't see any motive from Germanys side to support genocide on Palestinians. So my argument is essentially trying to understand why Germany would support Isreal despite . The only good explanation I've found is centred on "Holocaust guilt", and the way it's been portrayed and conveyed the past eighty years.