That alone doesn't really mean much though. Failure only breaks your ideology if you can't explain it using that world view. And you absolutely can explain the failure of Nazi Germany using an explanation consistent to the fascist worldview. It will be wrong of course, but when you've already accepted Fascism why would some shit like "Hitler lost because Stalin had some Aryan blood in him" sound ridiculous.

A lot of them also take a sort of "blackpill", knowing Fascism failed and will never happen all they can do is look back fondly at the "good old days" and wish they were part of em.