Infinity War had the unenviable task of bringing together more than a decade's worth of intersecting storylines while juggling 70+ characters. Now, a couple of deleted scenes from the movie reveal how differently the Incredible Hulk's trajectory was initially planned for the film, and made Smart Hulk a part of the storyline much earlier.
The first deleted scene takes place during the Wakanda battle between the heroes and Thanos' army. With Hulk refusing to come forth after his humiliating beatdown at the hands of the Mad Titan at the start of the film, Bruce Banner is forced to compensate by wearing Tony's Hulkbuster armor.
In the deleted scene, after the armor fails to match up to the combined might of the army of alien mutants, the Hulk has finally had enough, and Bruce transforms into his big green counterpart, bursting out of the armor and going on an unstoppable rampage. The Hulk then joins forces with the other heroes in pitched battle, and it is this scene containing the Hulk that was a part of the original trailer for the film, leading to anger and confusion amongst fans when the scene did not appear in the actual movie.
Another significant scene that was cut was when Hulk joins the other heroes a few minutes before Thanos' arrival. When Falcon and Black Widow mention the lullaby as a way to revert Hulk back to Bruce, the green behemoth responds in Bruce's normal voice, indicating that he has already transformed into Smart Hulk.
This was a significant departure from what we got to see in Avengers: Endgame, where Bruce Banner revealed that he had to undergo months of gamma therapy in order to finally gain control over his monstrous alter ego and become a true superhero with the power of the Hulk and the mind of Bruce Banner.
In both the deleted scene and the ones we actually got to see in theaters, Bruce's transformation into Smart Hulk happens offscreen. In case of the deleted scene, however, the change appears to have been much more instantaneous and without a very satisfying explanation for why Bruce would suddenly be able to control the Hulk's body. Perhaps that was why the makers decided to remove the scene from the film, and leave Smart Hulk's introduction until the next film.
Of course, this decision had the side effect of having many Hulk fans disappointed in the character's arc during Avengers: Infinity War, where he was brutally assaulted by Thanos right at the start, and then spent the rest of the film refusing to come out and lend a hand against the greatest threat the superhero team had ever faced.
And while Hulk did finally make an appearance in Avengers: Endgame, his biggest contribution was performing a snap while wearing the Infinity gauntlet and having a talk with the Ancient One about the nature of the time stones and what removing them would do to the current timelines. Quite a departure for a superhero who is exclusively known for destroying entire armies and cities and anything else that gets in his way single-handedly. This news arrives from ComicBook.com.