I think you may be reading too far into a FANTASY NOVEL... It's not indoctrination or brainwashing, it's a fairy tale.
On a side note, there are plenty of fan theories that talk about it all being in Harry's mind. Because he is always locked in the closet, he imagines a world where he is adored and powerful.
Just because a genre is fairy tale does not mean it cannot have ability to indoctrinate and brainwash. The indoctrination here is unintended as any story that directly reflects value system disorder of our culture/society. What is in this story is considered normal in our culture. From scientific perspective it's psychologically unhealthy behaviour.