These reports and interviews date back to June 2017 when we visited the set of Avengers: Infinity War, shortly after directors were chosen to helm the Captain Marvel movie.
Captain Marvel in Avengers: Infinity War, she’s not in the movie.
From what Avengers 3-4 writers Christopher Markus and Stephen McFeely tell us, there’s no character in the Marvel Cinematic Universe even on the same scale as Captain Marvel.
Perhaps it’s Captain Marvel’s insanely powerful abilities that help turn the tide in Avengers 4.