Warning! Spoilers ahead for Dragon Ball Super Chapter 82!
Aside from the obvious fact that anyone defeating an enemy except Goku would have broken a stagnant trope, the current fight between Goku and Gas would have been much more interesting if Buu had defeated the villain Moro from Dragon Ball Super's previous arc as was originally intended.
In chapter 82 of Dragon Ball Super's latest installment, Goku enacts a rather ingenious strategy using Instant Transmission to trap Gas on a faraway planet, believing that the villain wouldn't be able to follow him back. One of the places he leads Gas to is the Galactic Prison where the two interact with a few minor characters from the last arc—the Galactic Patrol Prisoner Saga. Although a pleasant nod to older enemies, this moment could have been much more ominous if Buu had successfully sealed Moro instead of Goku destroying him.
During the Galactic Patrol Prisoner Saga, Goku and his friends' original strategy against the rampaging Moro was to leverage the power of a god whom Buu devoured when he was still a villain. Long ago before Goku was even born, Moro was terrorizing the universe, and out of the many heroes who valiantly tried to stop the dastardly villain, only Grand Supreme Kai could defeat him by sealing Moro—who was then imprisoned at the Galactic Prison. Since Buu later devoured the Grand Supreme Kai when the Majin was still evil, it was theorized in the present day that Buu could leverage the Grand Supreme Kai's power to seal Moro away once more. But it unfortunately became apparent as Buu began fighting Moro that he didn't possess that sealing capability since it had transferred over to Evil Buu in Dragon Ball Z. As a result, the story eventually fell back on an old formula where Vegeta helped Goku destroy Moro for good.
In other words, since the Grand Supreme Kai is the only being capable of sealing Moro and Buu couldn't leverage that power, then the only way of defeating the villain was for Goku to completely destroy him. And by completely destroying him, Goku made it impossible for Moro to be imprisoned at the Galactic Prison for obvious reasons. Had Buu somehow found a way to seal Moro during the Galactic Patrol Prisoner Saga then the villain would have likely been stored away at the Galactic Prison like what happened when the Grand Supreme Kai defeated Moro originally. This would have created some major implications in the current saga when Goku eventually teleports to that very same prison with Gas. Instead of Goku and Gas conversing with minor prisoners as they do in chapter 82, Goku would have most likely found their arrival at the prison unnerving, knowing that Moro, who had been sealed by Buu, was imprisoned there, a realization that Gas could have exploited in some manner. Of course, this isn't to say that Gas should have somehow unsealed Moro then and there if Buu had sealed Moro away, but this alternative—or any alternative for that matter—would have been better than the embarrassing spectacle that actually transpired there.
That said, it would be disingenuous to disregard the massive strides that Dragon Ball Super has been taking recently to connect older mythos with the present day. This scene is undoubtedly one of these moments, but it's one of the more ineffective examples, especially since this connection only serves to remind fans of what could have been. The initial idea to connect Moro with Buu was actually quite inspired, but the delivery was off and this latest chapter now proves it. Buu should have either been first introduced at the very end of the Galactic Patrol Prisoner Saga as a successful last resort or revisited at a later time by somehow identifying a loophole within the Evil Buu conundrum. And this should have happened not just to make Buu the hero who saves the day but to reintroduce Moro later on in Dragon Ball Super.
