It's a Wonderful Life
Cynics did not love the ending of this classic feel-good Christmas story. With Uncle Billy not being held responsible for his foolishness, and a lot of financial problems, the whole thing was wrapped up with donations. Shouldn't Potter at least suffer some kind of consequence!
Fantastic Beasts: The Crimes of Grindelwald
Most Harry Potter fans either loved or hated this movie, and the ending was pretty tough. Queenie made a choice that was pretty opposite of her character arch. Plus, Credence as a Dumbledore turned out to be one of the lamest twists in the series!