I mean, if you cast Blanchett as the villain and you STILL can't make the character memorable, your movie's absolutely boned.
People (understandably) like to shit talk Shia but he was only a part of why that experience was lousy.
Considering that Crystal Skull was made by the original creators I'm gonna be charitable and say that Mangold wasn't really responsible for this movie getting a poor reception, but when you have four screenwriters and the movie still sucks, it's a sign the concept is pretty much done for.