Surprise, it was a Steven Universe episode all along!
I'm hoping there will be a chance for Vegito or Gogeta to appear in the Tournament of Power now that Kefla has appeared, the fight between Vegito and Fusion Zamasu was an awesome fight although I still dislike the retcon involving the Potara Earring Fusion.
Personally I don't have a problem with it as the whole Portora earring fusion in the Buu Saga felt like a big old plot cheat. Since it was established that dance fusion training takes so long to get right and requires a connection with the person you're doing with that they couldn't find the time to cram in once Toriyama changed his mind on who was going to take down Buu and just felt so haphazardly rushed in. And the whole "it will happen forever" thing just felt like trying to have consequences about it that Toriyama couldn't even keep up thus why Vegito wound up getting split up and... point is that was some pretty lazy writing on Toriyama's part that retconning it wasn't that big a deal. IMHO though now that we have another actual fusion as an enemy to defeat for the first time the process feels more justified honestly then it has been before.
The idea that Vegito's time limit ran out the second he let the barrier down inside Buu feels too much like a contrived coincidence to me in comparison to the initial reason given; the "magic atmosphere of Buu's innards canceled out the Potara Earrings' magic" explanantion felt like a reasonable explanation to me since Buu is a magical being
Hmm, the 1 hour time limit is out of the question. There is the extreme arrogance side effect or if they power up too far and negates the fusion. I guess either Goku will be forced to go to Blue and/or the fight might trigger Ultra Instinct again. But for the latter, we still don't have much info on it. Like we don't know how many times Goku can achieve it in such a short span of time.
Even though thanks to the Fusion, Vegito is also a magical being and obviously far stronger then Super Buu at that point