"Why does your goal of trying to limit their "manipulation" have more validity than their goal of limiting yours?"
Because Scientology's views aren't held in good faith and claims about society should be assumed to be pretexts used to justify the quoted excuse for predatory behavior. Scientology has a history of fraud, kidnapping, extortion, and other extreme exploitation and don't deserve any benefit of the doubt. Their views do have less validity since they're known bad actors.
I personally think they are kooks, and their views are less valid to me, but I also realize that it's just my subjective opinion. They also have the subjective opinion that their views are valid to them, and our views have less validity. No way to say who's "right", so they should be allowed to advertise until we agree on laws (still subjective) to possibly invalidate their views.
They are not mere kooks. They are an organized criminal enterprise. They've engaged in arson, kidnapping, extortion, attempted assassinations, money laundering, and other criminal acts. They are actively malicious and that's as realistic a line for dividing who is and isn't right there is.
Because Scientology's views aren't held in good faith and claims about society should be assumed to be pretexts used to justify the quoted excuse for predatory behavior. Scientology has a history of fraud, kidnapping, extortion, and other extreme exploitation and don't deserve any benefit of the doubt. Their views do have less validity since they're known bad actors.