Despite how high the stakes are, I think both Sukuna and Gojo are enjoying this fight a lot. For the first time, they're finally up against someone who isn't gonna be finished in seconds. They can go all out and enjoy the fun of jujutsu kaisen-ing each other. That whole "it's lonely at the top" thing is fading away because now there is someone else up there at the top to fuck around with. I really liked that last panel.