Sen. Clint Dixon, a Republican, said Willis was indicting Trump because of an “unabashed goal to become some sort of leftist celebrity” and should be investigated for using the justice system against her political opponents.
What the hell. It's literally her job to indict people who've committed a crime. Trump committed a crime, with pretty damning evidence and little room for interpretation. If they had counter-evidence to prove that Trump did not commit that crime, they should have brought it up a few weeks ago. If not, she was literally just doing her job.
I think the tribalism you describe is part of the explanation. Trump isn't just a member of their tribe, he's the strongman leader of it. They would make him their king because he wants to restore the old white Christian patriarchy. Threats to Trump are threats to that mission. This is what they mean by MAGA.