So, to your first question (about Antifa), MAGA don’t consider what the current administration (or anything they support) to be fascist. Because they tend to put the conclusion before the question: “I am against fascism. I support these policies. Therefore these policies must not be fascist.”

And because they’ve decided these fascist policies are not fascist, the term “Antifa” to them is similar to “pro-life” for pro-choice people. It’s a term that isn’t exactly accurate but makes the group naming themselves look like the good guys. And in the same way that pro-choice people don’t consider themselves “anti-life” just because pro-life people call themselves that, MAGA people don’t consider themselves “pro-fascist” just because Antifa call themsleves that.