Mommsen showed how the apparatus of the Reich worked.
Sofsky explained the regimes of terror of the Reich.
Kershaw summed all scientific controversies about the Reich up.
Arendt answered the philosophical question of how this was possible.
And Friedländer systematically mapped out the whole scale of the Shoah.

I suggest you to read Sofsky, Mommsen, Arendt, Kershaw and Friedländer. This requires some effort but you gain historical knowledge not depending on quotes of a senile war criminal.

I suggest you to read Mommsen, Sofsky, Friedländer, Arendt and Kershaw. Then you know why it will always be relevant.