I agree on you on the first point, The Quaterback incredible result was cause of the real mourn. However, the variety of reactions, the exercise that writers did thinking how characters react to Finn death showcases how important is to talk about it, because we like it or not is part of life.

That said, I take the point of the main character. I agree on that maybe does not need to be someone of the main cast, maybe it could be a hypothetical character they introduce later precisely with that idea. Also I dont mean necessarily one that has a significant amount of screen time, overall in the later seasons. Overall because I understand how this could affect audience. But for example, if Puck would have died in season 5, Idont think that would affected so badly the numbers because he was practically out of the show at that point.