Joseph is 100% correct. And while it is also true that far fewer people had advanced Torah knowledge than today where most everyone completes Mesivta and many spend several years in Beis Medrash and typically a couple of years in kollel, in kollel, the vast majority of Yidden, perhaps as many as you 80%, were frum and tremendous maaminim. To wuote Rav Yaakov ztzvk”l, emuna was taught to children while still in their carriages (i.e. they saw and heard living emuna.
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