Another example to prove the point: If it was revealed late in Inglourious Basterds that Hans Landa and the farmer from the first season had previously met in town and the farmer had revealed that he was housing people. It would completely undermine the character motives, the themes, and potentially the overall plot.
Yes, it's an "extreme stupid case", but there has been a lot of stupid stuff in movies and TV. I am baffled that you don't understand how later work can weaken the artistic merit of earlier works.
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Luster: Yeah, that's the most intense method of consuming cocaine.