No, the Rav didn’t make such claims and he was addressing a question from presumably a survivor looking for a serious answer. I agree with what he said, the question what caused the downfall of the European Jewish community is not yet answered. We usually associate both success and failure to a combination of leadership and mass Jewish response. See, for example, Shmuel v community on the issue of a melech. So, blaming erev rav is not a full answer. And I don’t think anyone gave an accounting of what went wrong with leadership and community. Currently, we have both mo and nonmo developed new institutions that we didn’t have at a time, but it is under cover of restoring old order (that failed)
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