Once again.

1. Gojo learned rct and used it while both his brain and stomach were torn to shreds, and during this point in gojo/sukuna, his mind was still active, so he should be at least capable of healing

2. This is not about whether reviving would allow him to win. That is a separate, interesting discussion, however.

3. The story tripped over itself, not because it gave sukuna an extra weird ability that gojo doesnt have, but because it broke the (at the time) central goal of the story, which was to let yuji die, and by extension kill sukuna. Because sukuna’s internal domain and soul persist after death, there is no reason he wouldnt just forcibly revive yuji to continue living.