The Russo Brothers say he doesn't even have the healing factor anymore. I think there are reasons why Thor and other heroes “feats” seem better or superior to Hulk's, which in turn, makes Hulk look weak. Hulk has been established as one of the powerhouses and strongest avengers in avengers 1 and 2.
Being exposed to so many enemies in the past, his journey through the space might have weakened the hero inside to the point where he could bond with Bruce Banner in Avengers: Endgame. That is what would have made the Professor persona turn much weaker in the MCU.
There have been criticisms about how the MCU has nerfed the Hulk, especially since he became more humorous as a character in the process. However, this change in power levels can be traced back to being Smart Hulk since Avengers: Endgame, meaning Banner has had a better handle on his emotions for quite some time.
In a new interview for WIRED, the brothers spoke about the controversial decisions they made to reduce the Hulk's strength and abilities in the colossal battle between Earth's Mightiest Heroes and Thanos. "We just didn't know what to do with him. We were like, 'What, this big powerful character.
In the MCU, why is “Smart Hulk” seem so weak? Because he controls himself. He does the comic book thing of restraining his strength so that the impact of his attacks seem lesser than what they might otherwise be.
But they didn't seem to be much use after he wielded the Infinity Stones, as his arm was left forever scarred. Well, Endgame directors the Russo brothers have explained just why the powers didn't work, admitting that the power of the Stones was just too great.
The polished fighting style of Thanos proved too much for Hulk and his overall brutality and savagery. Hulk had the upper hand for all of two seconds due to the element of surprise before Thanos was able to finish the fight with a few quick blows.
Out of all the Marvel movies and TV series the Hulk has been a part of, he never gets to tell his full story. Many of the problems with the Hulk in the MCU come from Bruce Banner's rights being all over the place when the franchise started. Marvel and Universal have different rights for this character.
Hulk's MCU downfall can be owed to Age of Ultron
The Hulk is supposed to be the most powerful in the MCU but this part of Avengers completely ruined that for all of us. His being under Wanda's mind control and then getting defeated by Iron Man raised a question mark on his powers.
Apocalypse makes his way into this position on the list because he is technically stronger than the Hulk. He also has a multitude of other abilities, including telepathy, telekinesis, and shapeshifting. And that's just touching the surface of his powers.
In the debut, Lee chose grey for the Hulk because he wanted a color that did not suggest any particular ethnic group. Colorist Stan Goldberg, however, had problems with the grey coloring, resulting in different shades of grey, and even green, in the issue.
In the MCU, Thanos is stronger than base hulk, but hulks whole gimmick is the angrier he gets, the stronger he gets. In a prolonged fight Hulk will beat Thanos, in infinity war Thanos is able to quickly beat hulk, but before hulk can wake up Heimdall sends him away, if he hadn't, hulk would have eventually won.
The amazing thing about the Hulk is that unlike nearly every other superhero ever created, the Hulk's strength has absolutely no upper limit.
The angrier Hulk gets, his mass increases in size in order to accommodate the increased strength. As Hulk becomes more powerful as anger increases, his strength continues to rise further and further. His rising anger allows him to literally beat his own power being used on him. Stated in official material as well.
So basically, Bruce Banner was unable to bring out the Hulk in Infinity War because he's been a lot happier/content lately than he was when he met the Avengers.
The first is a practical reason. Tony had only a split second to think before using the Gauntlet, and a snap is how Thanos and Hulk had done it, so it was the logical choice. Given time, Tony could have found a more dramatic way to get the job done, but a snap was the best quick solution.
Complicated Film Rights with Universal Pictures
Universal Studios would have lost the rights to the character if a new deal wasn't renegotiated. The deal was that Marvel Studios would finance The Incredible Hulk in exchange for Universal Pictures distributing the film.
Mark Ruffalo replaced Norton due to disagreements with the production company and so did Marvel studios.
ILM has a long history with the Hulk and during the production of Endgame they rebuilt their face pipeline to provide a remarkable digital character, a hybrid of Bruce Banner and the Hulk, that technically allows actor Mark Ruffalo to deliver a nuanced performance, that he had never before been able to deliver.
Joe: “Oh, we nerfed the Hulk. We nerfed him. We just didn't know what to do with him. We were like, 'What, this big powerful character.
Following the battle against the Avengers, all of Hulk's former teammates were either dead or captured. Hulk was met with the same fate as Thanos captured him beneath his own palace, turned him into a servant, and referred to him as a dog.
As much as Thor might protest, Professor Hulk lays a convincing claim toward the title of "strongest Avenger." Professor Hulk's base-level strength exceeds that of any other Hulk incarnation. Coupled with Banner's keen intellect, that makes him a formidable opponent.
Hulk is Stronger Than Juggernaut, But Still Can't Beat Him
When it comes to physical strength, Hulk has succeeded in demonstrating, time and again, that he might actually be the "strongest one there is" in the entire Marvel universe.