The posthumous “A Divine Madness: Rabbi Avigdor Miller’s Defense of Hashem in the Matter of the Holocaust” is Rabbi Miller’s justification of speaking the truth about the level of Torah observance in the period preceding the Holocaust. The Jews rejected the covenant, so Hashem punished them, exactly as He said He would.
If you agree with the above logic, however, then this applies equally to exposing the lack of Torah observance (including fraudulent workarounds) from way before the Holocaust, too…
Hyehudi.org writes about these problems partly in order to encourage change and to show rabbis cannot be automatically relied upon. But another reason is simply to justify the sufferings of the Jewish people; to defend Hashem!