yotsuya said:
And the words of Padme may be ringing in his ears, “there is still good in him.” Kenobi tells Luke that he once thought that as well, and this may be that moment. Even though Vader has just said he killed Anakin, Kenobi may not be ready to accept that yet. There are lots of ways to read this that make sense in light of everything else we have in the main Saga films. We don’t have to assume that Kenobi missed the perfect chance to kill him. Killing a being who is just one of many evils in the galaxy won’t change the evil of the emperor. And we don’t know what images of the future Kenobi might have seen that leaving Vader alive is the best option.You know, this would be great, fantastic stuff if the series bothered to show us any of that. If we got to see Kenobi try to bring Anakin back only to fail. This never actually happened, though. He beat him, said his friend was truly dead, and walked away. Hell, even Obi-Wan hearing the voice of Padme saying that would have indicated it enough but not even that is expressed. And considering this series is made for casual SW fans as well as diehards, something like that would have been warranted if they were trying to get that idea across.
There’s never an any actual moment that lines up with Vader saying Obi-Wan thought there was good in him. It wasn’t shown in RotS and it wasn’t shown here, despite you filling in the blanks for the writers who should have known better. If they had written it in a way that reflected what you wrote, it would have made more sense. But they didn’t, so unfortunately, all of this? Is you writing the script for them.
So what we’re left with is an Obi-Wan who seemed to have every intention to kill Vader, to the point of even landing a blow to his face, internalizing and vocally emphasizing that his friend is gone forever, DEAD, and then deciding to let him live anyway with zero indications of any potential thought to there being good in him still. Not even an attempt to convince him. The writing and directing do not reflect it, so there is zero reason to believe it.
JEDIT: And even then, I still think the confrontation should have ended with Vader escaping rather than Obi-Wan sparing him. It would have absolved Obi-Wan of the responsibility, even if he didn’t intend to kill him. Really, this whole show dropped the ball on that idea in general, tbh.
I think it is also important to consider, what a Jedi is supposed to do with Vader, if they are not allowed to kill their enemy once defeated. Particulary in the situation, where there is no option to bring him to justice, since the Emperor controls all branches of government. ROTJ makes it clear, that Obi-Wan and Yoda don’t believe Vader can be redeemed, so how is Luke supposed to stop/conquer them, if he cannot kill them? So, let’s for the sake of argument say Luke defeats Vader and the Emperor, and they are at his mercy. What then?