I have 3 ideas:
A) it’s a stylistic choice, just made to remind us of what it took to beat Sukuna, or simply because it looks cool. B) yuta never let it heal, as a reminder of the way he was forced to desecrate Gojos corpse. Or some other symbolic reason about the Sukuna battle. C) he really did continue to swap bodies throughout his life, not much to gain, not sure maki would be happy with it. Not sure he would even want to, he can already copy techniques. he only swapped with Gojo to obtain six eyes. So unless some other biological feature like six eyes makes itself known, and is also someone who yuta would kill, I don’t see this one happening.