In Shang-Chi and the Legend of the Ten Rings' mid-credits scene, Mark Ruffalo returned as Bruce Banner. Avengers: Endgame had established that the scientist had found a way to become a Hulk with his intelligence intact, so fans wondered whether using the Infinity Gauntlet had perhaps weakened the Jade Giant and permanently returned him to his human form.
We still don't have the answer, but footage from She-Hulk has seemingly confirmed that he will be back as Hulk in the Disney+ series. Now, the plot has thickened yet again with a claim from scooper MyTimeToShineHello that, "Hulk will leave Earth at the end of She-Hulk."
This was corroborated by another supposed scooper KC Walsh, and lines up with a leak of the Marvel Studios Spoilers Subreddit last year. Why would the Jade Giant leave Earth? Remember that it's previously been reported that She-Hulk is going to introduce Skaar, the son Hulk conceived on Sakaar in the Planet Hulk comic books.
This could definitely be enough to make Bruce decide he needs to return to the planet once ruled over by The Grandmaster, though Walsh would add that it's "A father and son round trip to get help." This suggests Skaar finds his way to Earth in She-Hulk, though your guess is as good as ours when it comes to what threat prompts them to leave the planet.
However, this could quite easily tie into those reports about plans for a World War Hulk movie!
Things should become clearer when She-Hulk hits Disney+ later this year, but it's beginning to look like the character will soon take centre stage in the MCU in a way fans have been longing for.