Russo explained that it was important for the filmmakers to revisit how the Hulk, for all his incredible power, paled compared to Thanos.
"We know how powerful Thanos is by his quick defeat of the Hulk in Infinity War, so this is an incredibly painful experience, to put on the gauntlet that controls the universe," Russo said. "It permanently damages the most powerful beings and some of the most powerful creatures in these movies, and very few people can actually put that on and survive."
Marvel Studios' head of visual development Ryan Meinerding also explained that in earlier development, they considered giving Hulk a more substantial injury in the form of physically shrivelling his arm, but ultimately abandoned the idea due to technical problems presented in later fight sequences.
"When Hulk brings everybody back with a snap using the Stark gauntlet, they wanted Hulk to have paid a severe price for doing it," Meinerding explained. "The idea of his arm being shriveled and messed up was where they were going with it initially, and... I pitched that basically when his arm gets shriveled, he just rips his sleeve off and turns it into a sling to allow him to fight later on in the film and not have that asymmetry be something that was too odd. In the end, they worked it out fine in the movie without that concept."
