If you know the holocaust is a myth, then the first sentences of the article take on a different meaning. Also note that fascism is usually used as a derogatory word for nationalism.
In 1945, as the news of organised mass murder and gas chambers shocked the world, the far right’s dream of a fascist future was left shattered in the ruins of Berlin.
The horrors of the Holocaust became the primary roadblock to the resurrection of fascism’s besmirched ideology. Many on the far right believed then, as they do now, that if fascism was ever to rise again then the truth of the Holocaust had to be destroyed.
The holocaust myth besmirched the ideology behind nationalism, and that's one reason holocaust denial is illegal. But the besmirched ideology of nationalism also paved the way for capitalism, and present day Euro immigration is directly related to laissez faire capitalism. It's cheap labor, it's more consumers, it all makes real estate rise in value. Besmirching the nationalist right, paved the way, not for the left, as much as it paved the way for free market, free immigration capitalism.
Another thing to add is the right has historically been a big part of resisting the holocaust myth. From Willis Carto in the late 1960's, but even earlier: Raul Hilberg commented (and I don't remember where) that in the 1950's in Germany he'd see far right papers with holocaust denial content. I'm not sure if the people writing in those papers and the articles they wrote, are even recorded in the history of resisting the holocaust myth. We have to learn of their existence from Hilberg of all people.