Most games today focus more on action sequences and explosions over an actual story. A perfect example is the Battlefield series. While there were many explosions in the Battlefield 4, it was evened out by the storyline.
Maybe GTA isn’t the best example with which to express fatigue for the open world genre, considering how the open world itself is probably the least exciting aspect of those games. Open world games should give players a lot of freedom while keeping them on a path where interesting things can happen.
Story is, in my opinion, far more important, because a good story is what gives a game immersion. People are relatively happy to solve puzzles for free because of intrinsic motivators.