Simple Denialism. It's completely dishonest but it happens.
If you can't agree on what the basic starting point of Reality/History is, then you can't have a dialogue about it. That seems to be what they want.
I thought this was an interesting reply. I was just going to say that they hate Jews, end of story, but I suspect Gracie MUST already know that, doesn't everyone?
Okay, what is the starting point of reality, or the starting point of history? The starting points changes radically from time to time. Such as whether Roman emperors were REALLY gods........they spent a lot of money building temples to some of them, and enforcing worship. The examples multiply. Consensus in Our Time, maybe, is the starting point of history. The consensus of the moment is that the Murder of the Six Million happened. I suppose lots of people try to undermine consensuses all the time, such as that weird NYTimes idea that the U.S. was really founded in 1619 by slaves, or something. Or that men can turn themselves into women, that's an attempt to undermine a consensus about reality. It's true we can't really have a dialogue about those things.