I feel like by condemning the ideology that something is (fascism), you’re condemning the party or movement itself too (Nazism)

Feelings aren't facts. Feel whatever you like. That's called an opinion. The fact of the matter is that there are fringe groups associated with every political party. The vast majority of those with "MAGA/Ultra-MAGA" philosophies condemn Nazis. They also condemn Q-Anon, Antifa, and many others. Many condemn the actions of those at the Capitol Building on January 6th.

You're choosing to ignore the existence of the majority for the sake of your argument.

For example: the statement, "All individuals that supported the 2020 protests are Antifa, a violent extremist group" is inherently false because the majority of individuals that supported the protests believe that they were mostly peaceful.