Wow that's a huge jump from your Infinity War rating. What was the cause?
Endgame is by far my favorite MCU film (I haven't been a huge fan; enjoyed some, hated many). Whereas Infinity War was an interminable slog of endless, artless, pointless CG action scenes (it felt like watching someone else play videogames for two hours), Endgame told an extremely compelling story chock full of wonderful character arcs, actual stakes, and emotional payoffs that far exceeded my expectations. The first hour was phenomenal, the second a very enjoyable piece of fan-service and cute riff on Back to the Future Part II, and when the action extravaganza finally arrives in the third hour I was so engaged and hyped for it because the movie actually did its job by setting up a compelling drama and paying it off in spectacular fashion. I loved it.