That's more-or-less the plot of the movie "The Brainwashing of My Dad". The Dad in question is interviewed in the film. He is generally aware of what happened and happy about the situation.
Is that a guaranteed result? No. But it's more likely than you might expect.
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The problem in these scenarios turns out to be that people aren't "brainwashed" or delusional or psychotic; but that they spend enough of their attention on bullshit that the bullshit feels like their identity.
Is that a guaranteed result? No. But it's more likely than you might expect.
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The problem in these scenarios turns out to be that people aren't "brainwashed" or delusional or psychotic; but that they spend enough of their attention on bullshit that the bullshit feels like their identity.