I’m not sure you can map one side onto the other particularly consistently, but I think there are big historical parallels with groupthink.
Last year I read the Wolf Hall trilogy (for those who don’t know, set under Henry VIII at the start of the English Reformation); and I also read Life and Fate, which is a sort of 20thC War and Peace, set in and around the battle of Stalingrad, by Vasily Grossman, a Ukrainian.
I was struck by the parallels in both with groupthink, right think, what you are and are not allowed to think or believe or say in public, the threat of violence otherwise, the way that subtly silences people and has a « chilling effect » on your actions. There was also a lot of the official line changing and « we have always been at war with Eurasia » stuff - what you believed yesterday has to be updated now. In Wolf Hall things like indulgences, transubstantiation and not allowing people a peek at the Bible all smack of TRAs, but as pp have said, there are lots of unintended consequences, like the closing of convents where women were left alone and Abbesses could be powerful and independent. (I think we got off lightly when you look at Europe, where a good 150 years of war bubbled on). In Life and Fate, it’s clear you only got on if you parroted whatever Stalin thought, even if that was anti-science and the opposite of what he said the day before.
I thought a lot about trans narratives and methods, and how power silences its enemies. It was revealing to say the least. This is why authoritarian governments don’t like to teach history unless it’s completely on their terms - people learn to think independently.
So it’s hard to map one on the other OP but you’re not the only one to look at previous situations in history and think « Oh, look at that, they’re doing it the same way! »
I think the opposite of fundamentalism is education, science, free speech, and tolerance (to a point, where it becomes defence of rights and spaces). That the TRAs mess so much with all of those is what makes me so furious.