What you are all missing is the biggest blunder of all with the movie/book series. If Hermione had the Time-Tuner in The Prisoner of Azkaban which she got from Minerva McGonagall, and which Professor Albus Dumbledore knew about because he told them to use it to save the lives of Sirius and Buckbeak…
Why in the world wasn’t it used to go back in time to stop him from poisoning himself. Or from any of the other steps that led to Professor Dumbledore’s death. It could have totally been prevented.
Furthermore they could have prevented the attack at the wedding, the ambush at the ministry of justice, and on and on.
It is the one gigantic flaw that she opened herself up to when she introduced time travel into her series and then just magically makes it go away and hopes that no one thinks about it anymore.
After receiving the series as a present for the holidays and my kids watching them over and over, these things have become more irritating each time we watch them.