No, fascism has a pretty clear definition, just read Ur-Fascism. DHH fits that to a T. You just don't know what fascism is, or you're struggling with some cognitive dissonance.
DHH repeatedly presents electoral democracy as the legitimate mechanism for resolving political disagreement. He has also repeatedly emphasized free speech, including criticizing European restrictions that he regards as excessive, and has argued for keeping political disagreements from destroying ordinary social relationships.
Historians generally use fascism for something considerably more specific than nationalism, anti-immigration politics, or right-wing populism: typically an authoritarian ultranationalist movement hostile to liberal democracy and political pluralism, historically associated with a powerful centralized state, suppression of opposition, and political violence.
DHH doesn’t fit the bill.