Many of his extended family didn't make it.

He has mentioned this. Perhaps you missed it. It's personal, on top of being rather an important chapter in racist history.

The point here is, I think, that while the violence and death are just as atrocious under Communist regimes, those atrocities were done for political purposes, and were the means to an end, a tool of policy to consolidate power and crush the opposition. While this behavior is horrifying, it's hardly surprising.

The Holocaust, as one can plainly see by the accelerated use of resources needed to prosecute a war going badly, was an end in itself. The Holocaust was a major policy objective, planned far in advance and pursued even when Germany itself was under attack. The Nazis even developed special Holocaust technology expressly used for extermination. This makes it unique in the bloody history of mass murder.

It's not merely --merely-- a question of headcounts in the murder business, but the fact that an industrial method for exterminating people based on their genetic heritage was developed and employed. There have always been mass killings based on political activity (including religion), and mass imprisonments based on the same thing. There have been massacres based on race and nationality, usually by mobs or soldiers in berserker mode. There are even examples of an imperial power depriving a subject people of food for political and economic reasons, thus murder by famine, before the Ukraine (though not on that scale). But never has there ever been the cold-blooded factory-facilitated processing of murder on this scale, planned and conducted in the heart of an otherwise educated and civilized nation over a period of almost a decade. If Communist victims went like lambs to the slaughter, Nazi victims went to the sausage factory.

I'm not even sure this is about the symbols. It's more about the nature of the history itself.