I honestly don't think Brie Larson's acting in Captain Marvel was all her fault, I feel like it may have been more of a director issue. When it comes to Brie Larson, she has proven time and time again that she can act really well and from the little we saw of her in Endgame, she seemed more in character then than when she was in Captain Marvel. Keep in mind, I haven't seen the whole film, just clips, but it definitely strikes me as more of an issue with how the director wanted her to act over how Brie Larson wanted to portray Captain Marvel. With the new director on this film, I have high hopes we'll see improvement.