Marvel's What If...? has been exploring the multiverse by showcasing non-canon "what if" scenarios throughout multiple points in the Marvel Cinematic Universe. The recent episode explored one particular big week where one thing happened right after the next. In doing so, it inadvertently re-canonized one MCU movie that's been up for debate for years.
The Incredible Hulk, the second MCU movie ever released, is often forgotten about by both fans and Marvel Studios itself. Due to the character's film rights being owned by Universal Pictures, Disney can't even put The Incredible Hulk on Disney+, only adding fuel to the belief that the film is not canon. Marvel's other reason for distancing itself from the movie seems to come from the recasting of Bruce Banner from Edward Norton to Mark Ruffalo. Ruffalo's portrayal of the character has been widely acclaimed, leading to Marvel focusing on his rendition over the original.
Fans of the Green Goliath's movie can rest easy knowing the film still resides within the MCU timeline. Episode 3 of What If...? titled "What If... The World Lost Its Mightiest Heroes," takes place during the events of Thor, Iron Man 2 and The Incredible Hulk, which all occur within the same week. Focusing on the events of The Incredible Hulk means Marvel is willing to confirm the movie is still canon to the MCU and that Hulk's origin didn't change after the recasting.
There's been evidence of The Incredible Hulk's canonicity for years, though. General Thaddeus Ross, the overarching villain of the movie, has made appearances in other MCU films, even playing a major role in passing the Sakovia Accords in Captain America: Civil War. Bruce referenced his battle with the Abomination during his conversation with Steve Rogers in The Avengers. Abomination himself is making an appearance in the upcoming movie Shang Chi and the Legend of the Ten Rings and was even considered at one time for the Avengers Initiative.
Yet detractors of the movie like to call into question its status within canon. Partly, this is because the rights issue that has kept the movie away from Disney+ isn't as well known as the ongoing tug-of-war that is Sony and Marvel's battle over Spider-Man's film rights.
This isn't the first time Marvel has gone back to works of theirs that weren't all that well-received. The timeline of Thor: The Dark World played heavily into the events of Avengers: Endgame. Thor and Rocket went back to that time to obtain the Reality Stone, even encountering Thor's mother Frigga, in a rather touching moment.
Marvel Studios has always done a good job of standing by their established movies, even if the movies weren't what fans wanted. What If...? gave The Incredible Hulk a chance of redemption for older fans while also presenting it as an option for new fans to watch. It's possible What If...? will provide more of these redeeming moments for the MCU movies fans love to hate.