It's a different style of Marvel movie, with a lot of story. It's an ensemble movie that doesnt build up with multiple movies like avengers, doesnt get it right like guardians of the galaxy, but definitely doesn't get it wrong like suicide squad 1.
In the end I think it was really good but really long. It's one of those movies you have to watch multiple times to get all the lore, to get all the implications in the marvel cinematic universe, and to get to appreciate all the future payoffs it will have in the future. I think it's just different from the typical marvel formula which is why it's so criticized so much but I think in the long run it'll age well.