A thoughtful and thought-provoking essay. Well reasoned and cogently presented. Hats off to you, Adam.
There was a time when readers expected stories to teach moral lessons. I'm glad that time has passed. I prefer stories that expose society as it is, in all of its complexity, ambiguity, and human contradictions.
I also appreciate your advocating for the writer's integrity--his/her obligation to tell the story as it should be told. Characters must be developed with complexity that shows their humanness. The plot arc must follow the beats and guide the tension upward to the climax. The denouement must offer satisfying answers to the story's driving questions.
Hence, despite Ringwold's hindsight-driven objection, I agree the scene is necessary.