My experience with Leftists is that they refuse to read, listen to, or watch anything that deviates one angstrom from their angry Marxist world view. Don’t bother trying to change their inflexible minds.
This is correct.
Refer to Yuri Bezmenov, a Soviet defector.
He said you can show believers the concentration camps, the graves of the victims yet still they won’t believe until they are kneeling before their graves with a gun to their heads.