There has to be some latitude given here. They can’t possibly, for instance, know exactly what was said or who interacted with who and when with any reasonable certainty. It’s usually “John met with Ted and I think Sally too, he told them to fuck off because it was a bad idea.” Now make that a scene and stay accurate.

Rarely are these things documented in the moment and human memory is fickle even when we think we recall something accurately. It may seem like I’m taking y’all too literally or being nitpicky but I’m just illustrating one component. These kinds of situations happen across every “fact” of the story, which is almost always a movie based on a written account that came after, often written by someone who wasn’t even involved in the subject matter. Degrees of separation, lack of information, some or all people involved may be dead, etc.

There is no data to support your last paragraph. But it is fun to talk about how dumb the “other” people are.