I believe political scientists landed on latent racism to explain the rise of Trumpism because the economic analysis doesn't explain how many of his followers weren't lower-middle class. Trump spoke as an economic populist and as a racist, so he captured different segments of the public, but the racism stuck because his interest in fighting for the little guy is obviously superficial (since he's a textbook malignant narcissist).

But that's not to say that Trumpism is equivalent to white supremacy. Racism accounts for the cult's original driving force, but currently the conservative/masculine cult is animated by anti-Wokeness (anti-toxic femininity).