ensemble cast, the ensemble is getting so big that it gets hard to keep track of everyone and care about everyone. Avengers: Endgame handled things great by focusing in on the OG Avengers (Iron Man, Captain America, Thor, Hulk, Hawkeye, and Black Widow) in the midst of a much larger ensemble. I think part of what has gone wrong in Phase 4 and beyond is that the universe has exploded to be so large and there are so many characters and side plots and storylines going on and viewers are having a hard time on finding a cohesive core story (and some of the characters that may have been tabbed to be the new "core" like Captain Marvel seem to have been rejected a bit by viewers).

I think the hope is (at least for me) that maybe the MCU is able to build some cohesive teams and rediscover a new "core" that they are able to hone in one and focus as the key core of whatever is happening in Phases 5 and 6.