When we argue a point, we often say things like, "I could be wrong." We say that, but do we really mean it? Many people experience something called "naive realism," and anyone who argues about genre shows experiences it often.
It's not unusual to come across naive realism in regular life. The words "naive realism" were coined by a group of psychologists studying how people perceived situations. The tenets are simple. We are unbiased observers, who see events and interpret them without any kind of prejudice or filter. Any other rational person, looking at the same events, would interpret them the way we do. If anyone doesn't interpret them the same way, they are biased, stupid, lazy, or somehow cut off from seeing the real situation.
The scientists tested this by asking volunteers to participate in a game - the old Prisoner's Dilemma. If two people, isolated from each other, agree to cooperate, they both get a small reward. If one cooperates and the other doesn't, the one who doesn't gets the reward, and the one who cooperates gets nothing. If both of them refuse to cooperate, they both get nothing. The scientists got college students to participate - but only certain students. The students were selected, by their dorm leaders, to either be the most likely cooperators or the most likely non-cooperators. The scientists described the game to the students, but some students heard it was called the "Wall Street Game," while others heard it was called the "Community Game." The Community people were twice as likely to cooperate with each other as the Wall Street people were. There were no differences between the play of the people labelled cooperators and those labelled the non-cooperators. The dorm leaders certainly could have been wrong about the character of the people, but the biggest factor was in what the participants thought the game was "about." If people thought the game was a cooperative game, they tended to cooperate. If it was a competitive game, they competed, and didn't see why anyone would do any differently. Two different groups of people had entirely separate views of the same game.
We see this in politics a lot. People will look at the same situation and differ utterly, and sincerely, as to what caused it and what the best course of action to solve it is. The same situation will seem to be "about" different things. But politics is rancorous and complicated. What strikes me is how often I see this exact mindset when it comes to genre fans. In this case, everyone is being presented with the same information, and seeing it completely different ways. One person's cruel trick is another person's playful sign of love. On person's significant look is another person's distracted glance. One person's villain is another person's hero. When have you come across this in fandom?