“We didn’t hear the whole story during the Holocaust.” (emphasis mine).

It seem mean in the sense of back then people weren’t hearing about what was going on in near real time, and only afterwards was the full dimensions of the horror discovered.

Mind, you don’t think we are hearing the whole story of this Holocaust in near real time either: it’s not for nothing that Israel has blown up the Hospitals (were the dead were counted), has murdered over 1000 journalists and is blocking aid organisations from entering Gaza - all of which to block people outside from knowing the full scope of what the Israeli are doing in Gaza.

We are hearing enough to know its a Genocide, but the full dimension of the thing (possibly with it, in scope and in methods use, already being or well on its way to be a new Holocaust) will only be discovered later if at all.