The thing about conservatives and their conspiracy theory that "the libs" are trying to brainwash their children is that a) it's entirely 100% projection and assuming everyone operates the way they do, and b) what is actually happening is more akin to deprogramming than brainwashing.
Speaking from experience, growing up in a conservative family and community was a continuous, painful process of having my natural compassionate and empathetic responses stamped out of me.
I was constantly discouraged from seeing the humanity in others who didn't share my race, class, religion, or my parents' political beliefs. I was shamed and punished for every thought and action that didn't align perfectly with said beliefs. I was taught to avoid any information that contradicted those beliefs, and to fear and mistrust it if I couldn't avoid it completely.
And this wasn't done by providing all the teachings and then holding me to them, mind. I never recall having anything truly explained to me. No, the method of instruction was to wait for me to do something that fell outside of the narrow guardrails no one had ever shown me, then yell and pearl clutch and bombard me with horror and disappointment that I had said/done/thought such an "awful thing." Again, without ever explaining why it was awful.
This process gradually taught me to view the world primarily in terms of my own emotions, and to view those emotions as the voice of God--as long as they aligned with conservative values. And since I was being trained like a dog to experience discomfort, shame, fear, and distress whenever I encountered anything or anyone that didn't align with those values, I was basically innoculated against critical thinking and basic facts.
The result of all this was twofold. Firstly, though I didn't stop having questions or doubts about the ideas I was being taught, I felt intense guilt and shame whenever I had them. Secondly, I began to perceive anyone else questioning my beliefs as an attack on everything I was.
The last thing that was done to me--by parents, teachers, preachers, and eventually friends, because we all learned to do it to each other--was to make me acutely aware and terrified of how my community would see and treat me if I ever strayed from the beliefs we now shared. After a lifetime of being trained to hang my entire self-worth and moral compass on how conservative authority figures reacted to me, I was presented with an image of lifelong shame and disappointment. Utter loneliness. A chasm between myself and everyone I knew that would never be bridged. And of course, eternal suffering and separation from them after death.
Yeah, the death-cult of Christianity was a whole other can of worms on its own, but its lessons and methods ultimately reinforced the conservative brainwashing, and vice versa.
In contrast, becoming a "liberal" (read: someone whose beliefs are rooted in facts and who cares about people more than ideology) was a very internal, very self-guided process. Nobody was actually pushing me to believe one thing over another. What actually happened was: I got distance from that community and their constant reinforcement; I got access to the information that I was kept away from as a child; I encountered people with different views and backgrounds and saw that they weren't evil monsters; I was encouraged to decide for myself what I thought, and learn to defend that thought with information.
And yes...that did lead me away from the conservative beliefs of my family and childhood community. Because those beliefs could not stand up to the smallest amount of critical thinking or actual facts.
It still took me over a decade of being separated from that community to unlearn all of those trained responses. Hell, I'm still unlearning some of them. I still struggle with the loss of that community. I still have an intense emotional reaction I have to work through before my thinking kicks in, whenever I am presented with information that contradicts what I thought I knew. I still come across thoughts or negative associations I have with various people, ideas, etc. only to realize those are unexamined holdovers from my upbringing. Like moving a piece of furniture and finding all the crumbs and other nastiness your vacuum's been missing.
But the key thing here is, the process of becoming who I am today wasn't brainwashing. It wasn't even, now that I lay it out, true deprogramming. It was more like recovery. A long and arduous process for which I often needed support, but which was ultimately completely led by and up to me. I had to want to get better. And I did. So I did.
Which is why I can say for certain that what conservatives are doing now is absolutely 100% about removing as many avenues as possible for doubts and questions to lead to critical thinking. That's why they're hamstringing teachers, banning books, pushing revisionism in the teaching of U.S. history, attacking queer children, doubling down on anti-intellectualism, deregulating child labor. They know that exposure to diversity and access to real information and education is a tried and true path out of their cult mentality. And they can't allow that path to exist.