I guess that’s the thing I’m still struggling with. Even if that’s the case that Kenobi and Yoda aren’t telling Luke explicitly to kill Vader in RotJ, I still have a hard time believing that Obi-Wan wouldn’t still end Vader in this show. He KNOWS what Vader has done and is capable of, he can see how much he’s suffering and he has to know that it’s his fault for leaving him alive on Mustafar. Especially after internalizing that his friend is truly dead and consumed by Darth Vader, Obi-Wan has every reason to mercy kill him. They could have easily written it in a way where the two get separated in their duel and make it impossible to finish it so Obi-Wan flees back to Tatooine, but no he intentionally lets Vader live. It doesn’t work for me.

Obi-Wan would especially see Vader as his responsibility to finish. Letting him live makes him look extremely irresponsible and foolish, to a point that I feel os incongruent with his character.