Remember there are are radical nationalist / racist / xenophobic groups in germany / anywhere.

Such groups are so strong in Germany that Hitler used them to strenghten the power of his discourse.

Recognizing Israel / the Jews are the ones now doing Genocide would *in the sight of the extremist groups* prove their belief that Hitler was right / the Jews are the devil. (I repeat, in their regard, not mine)

Therefore, my opinion is that the official stance in Germany must be "historical responsability" mainly not for the sake of the Jews, but for the stability of the society.