No, Marx didn't say a million deaths was just a statistic. It was instead the cuddly teddy bear Joe Stalin, and what he said was, "A single death is a tragedy -- a million deaths is a statistic." Maybe he meant that the more deaths one confronts, the more numbing it gets. Or that it rips you apart when it's someone you know, but it doesn't touch you when it's a newspaper headline. Or maybe he just meant that he was a homicidal paranoid lunatic.

Re the pandemic: the longer the pandemic goes on, and the greater the numbers get, the less it touches people (often). But it it's anyone we know, it hurts us, every one.