For whatever the reason over the course of time I've seen all the MCU films, and holy shit this movie sucked. Sure part of it was the hype, the cliffhanger ending set up a lot of expectation for the next film. Even so, they just didn't do anything with the hype. You'll see a lot of people nit picking at the plot holes, yeah, sure, there's tons of huge gaping plot holes, but there were huge gaping plot holes throughout the series. Get over it, that alone doesn't make this movie in particularly bad. The only one that really bothered me in this film was Thanos being just as powerful- no he was more powerful without the glove than with it. The dude fought all the Avengers at once and almost won in this movie, whereas Infinity War he fought like 5 of them and should've fucking lost.
No, the plot holes aren't what get me going about this film. It's the story itself. It's an homage to itself. "Lets show every character we can and briefly touch upon every storyline in every movie and not tie them together in any meaningful way other than, boom, time travel. There's no building suspense or tension. Like in Iron Man 2, Tony was going through some shit and had to get a new heart. In this film they encounter problems, they briefly talk about it, then they fix it. When they get into a problem the movie stops, they talk about it, and then they solve it with basically no issues. There's no drama or suspense. It's boring.
The fight scenes were few and far between. They didn't even fucking fight. And when they did it wasn't fun looking. Nothing entertaining happened.
It's like the writers and directors knew this movie would make a billion dollars so they said, fuck it, we don't even have to make a good movie. Lets just shit out some gold and call it a day.