In the language of the progressive, "Fascist" mean "anything not in line with progressivism." Doesn't matter that the truckers want less government control, which is categorically counter to fascism. It's the same line of reasoning to justify not listening to women or minorities when they have opinions counter to their own, or how they can be "pro-working class" yet hate actual working class people.

Oh THAT'S the original version of the cartoon?

…wait, how are they Fascists? Trump I could at least see the logic on, as he was the government at the time, but the truckers are specifically telling the government to go "fuck themselves running into a lake full of rabid geese." That's the exact opposite of facism.