But as Mark Ruffalo says, his character has now seen things that Hulk was never privy to while contained to our planet, and his world-view… er, universe-view has been drastically altered.
He’s not going to go along with whatever Tony says as Avengers: Infinity War is getting underway.
Bruce Banner probably still distrusts Tony Stark for lending his hand — inadvertently — in the creation of Ultron, a menacing program that took sentient life and threatened our entire planet.
Tony still seeks a way to protect Earth from a threat that he knows is coming from above.