It should. Too often though the victims of manipulation are also manipulated into believing other people telling the truth are lying or people trying to help are actually the ones manipulating the victim. Cognitive dissonance is a real thing. It’s like if someone believes the earth is flat because they were manipulated into believing that, along with being told the evil government is hiding the flat earth truth from them. Then, if the government offers irrefutable proof that the earth is round, the victim might categorically dismiss that proof as propaganda. This further drives them into this manipulation. And it can make it even harder to get through to them.