As noted by Thor in Thor: Ragnarok, Hulk was the "stupid Avenger" and as we all know he really wasn't that smart in all the movies he was in - up until Thor: Ragnarok where he suddenly seems to be speaking in semi-intelligent sentences. My question is, how and when did Hulk get so smart?
According to director Taika Waititi, just in time for filming1.
1And by that I obviously mean, while on Sakaar.
In an interview with CBR, Taika Waititi revealed that Hulk's time on Sakaar allowed him to become more comfortable in his green skin and learn about himself:
Yeah, that was really, just like with Chris, just wanting make it more interesting for Mark to play that character, because in the films he just said one or two words and just destroyed everything, and that was the version of Hulk I think that everybody knows.
But this version -- the smarter version -- it's just become so much more interesting and engaging, because he's been the Hulk for two years. He's a hero on this planet and he's had more time to just sit with himself and feel comfortable in his own skin.
Thor: Ragnarok’s Smarter Hulk Is ‘Comfortable in His Own Skin’
On the same note, some of the features of Hulk's new "bachelor pad", namely the hot tub, aren't simply for him to splash about in, but used by Hulk to have moments of introspection.
Now you can see Hulk sitting still and being kind of like a big silverback. There’s there’s this moment when he’s in the hot tub in his apartment – he just feels like General [Colonel] Kurtz in Apocalypse Now. He’s just sitting there, just contemplating things and you can feel him probably ruminating over all sorts of stuff inside his head. And that introspective, that very still version of Hulk, I think is way more fascinating than the guy that just destroys everything.