This article focuses on generalities. The more specific problem is the same one W.E.B. DuBois grappled with in his book Black Reconstruction in America: Why does the White Working Class consistently vote and agitate against their own self-interest? Part of it is race - they are either convinced that their problems are due to "other" workers, or that they are at least "better than" than "those" others. Part of it is that capitalists have effectively inoculated their workers against "socialism" - anything which is labeled "socialist" is automatically rejected in the same way that our anti-bodies attack anything deemed to be foreign.
The solution should be to speak to the real needs of white workers, and show how solidarity with other workers is to their common interest. Bernie Sanders started to make headway on this path. The question is whether the Democratic Party can re-make itself as the Party of and for workers.