Sukuna is soon going to start the merger because he is weak rn just like he did with Gojo and summoned mahoraga, To defeat the merger Gojo(one eye sacrificed to adjust power scaling)came because we know its nearly impossible at this point to defeat the merger and Sukuna at the same time, soooooo.......for the sake of the plot Gege revived Gojo just to fight the merger and Yuji fighting sukuna , this way the build up of Yuji's character won't get ruined; THE GHOST OF THE STRONGEST; JJK MANGA IS THE MOST TRENDING MANGA IN THE WORLD RN; AKARI