You want to say that the dispute here is over ignoring objective facts, but it isn't. I haven't seen anybody here ignoring the facts laid out by this article.

The dispute is instead about statements just like your We don't know why Altman referenced "Her", which, on the one hand, you're right, the mind of another personally is technically unknowable, but on the other hand, no, that's total nonsense, we do indeed know exactly why he referenced the movie, because we're a social animal and we absolutely are frequently capable of reasoning out other people's motivations and intentions.

This is not a court of law, we don't have a responsibility to suspend disbelief unless and until we see a piece of paper that says "I did this thing for this reason", we are free to look at a pattern of behavior and draw obvious conclusions.

Indeed, if it were a court of law, that's still exactly what we'd be asked to do. Intent matters, and people usually don't spell it out in a memo, so people are asked to look at a pattern of behavior in context and use their judgement to determine what they think it demonstrates.