I think a lot of the white dudes who participated in "nerd" cultures while growing up in the 2000s really internalized the idea of "being a nerd means to be shunned by society." So when they hear that they can't be oppressed because they're white and male that contradicts directly with their worldview because honestly they were probably bullied as kids and probably do go on to work legitimately oppressive jobs at some point in their lives.

The fascists did a better job articulating to them why their lives were so shitty. It was easy because it was the first time everyone in the world had access to the internet on their smartphones and no one had developed an immune system against online reactionary rhetoric yet. That's the main problem I think.