Trump is called a fascist not because of his conservative/traditional rhetoric. In fact none of the alt-right are THAT conservative. I mean, Trump himself is a pretty liberal cosmopolitan playboy.
The accusation stems from his lack of respect for democracy, rule of law and his fascist behavior. Trumpism is a fascist cult in all aspects. The movement has no real coherent ideological basis. It's literally a cult of personality surrounding Trump.
There is no "recent resurgence".
I think the bottom line is, you have to unlearn a lot of the just-so narratives that you have been taught about the world.