This one time my dad was talking about Karl Marx and said he was “born in Russia”, and I corrected him that he was born in Germany. And then he got argumentative and started spouting out other facts about “Karl Marx”, like that he overthrew the Czar and lead the Red Army…
Suddenly I realized… “Dad, you’re thinking of Vladimir Lenin, not Marx.”
My dad realized I was correct and replied: “Well of course you would know that.”
I really don’t know what it is, I guess maybe they think I’m joking or being hyperbolic? It’s odd though, you have to explain you believe this stuff three or four times before anyone starts to act like it’s sunk in.