Avengers: Infinity War’s commentary explains what’s up with the Hulk
https://www.polygon.com/2018/8/1/17638702/avengers-infinity-war-hulk-thanos
The Hulk refused to show up in Avengers: Infinity War after being defeated by Thanos in the opening moments of the film, but his absence wasn’t due to wounded pride. The movie’s creative team has clarified that the Hulk is working through his place in Bruce Banner’s life, and for now that doesn’t include saving the day whenever Banner needs a problem solved.
[Warning: The rest of this article is going to feature heavy spoilers for Avengers: Infinity War past the first few minutes.]