In a nutshell: suspension of disbelief in storytelling only works if the set of unrealistic rules is clear, well-expressed early on to the audience, and nothing later in the story comes too strongly against it.
For all that John Lasseter turned out to not be a very good person, he had that fine line down to a science, it’s fascinating to read interviews about his approach to it. In particular, Toy Story was a hard exercise in it, because there are many things that make its mythology somewhat contradictory. But people actively want to believe, so when it works and the line is well-balanced, the payoff is huge.
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