For a movie supposedly so driven by characters, almost all characters' actions feel weightless and in service of the story, a sloppy and inconsistent story at that. How do you write a movie with only two character deaths yet you only show the aftermath of one? You have to be utterly incompetent. They could have easily made it a two-in-one funeral. Another great example of horrible character writing is when Thor decapitates Thanos, the man that killed half the people Thor loves and that he barely failed to stop. You know what the reaction by him and his teammates is? It's a one-liner. And that's it. That's it.
Then you have Thanos whom not by intelligence or ingenuity discovers the Avengers' plan, but by deus ex machina, a contrived Wi-Fi hotline that connects the two Nebulas and proceeds to spew exposition. You know what Thanos does with this information? He sits his ass down on a stump and waits for Nebula to do all the work. Thanos also somehow becomes more powerful than ever without the Infinity Stones, despite what Thor did to him in the very beginning of the movie.
The action is, of course, mindless CGI that more resembles a video game than real life. That would be fine if the movie were animated—like Into the Spider-Verse, a better movie with better action—but it's not. It's live-action; or, at least, it's pretending to be. You see a real Robert Downey as he drives a horribly faked Audi straight from Forza. The juxtaposition kills any immersion or viscerality in the action and movie as a whole.
If the movie is so great because there's so many characters juggled, then I would posit that Crash must be one of the best movies in that case. A movie isn't good just by virtue of barely managing to juggle a massive ensemble over a story with nearly six hours of runtime.
The score is barely worth mentioning—it's unmemorable, repetitive, and genric, the only interesting parts being imitations of music from the original The Avengers, which didn't have particularly good music either. All other tracks are monotonous and unmelodic horns blaring.
If Spider-Verse isn't your cup of tea and you don't believe it's better, then try Spider-Man 3, because even that's better.