The only complaint I’d have with the inclusion of the line from rebels is the part that says “I destroyed him”. Within the context of the movie, and having watched ObiWan basically defeat and humilliate Vader only 10 minutes before, that part of the line sounds as Anakin rationalizing and making up for his failure in his mind.
But answering Anakin Skywalker was weak alone isn’t complete neither.
I remember there was a video made by TheCutter where he used another line that, when asked “anakin, can you hear me” went more or less like “that name no longer has any meaning for me. Now I know the power of the dark side” (and started crushing things). Perhaps if you added “anakin skywalker was weak” instead of the line borrowed from ROTJ could preserve the meaning and loose the pretension of Vader having the psicological structures of a weak person (esencially saying he won when he clearly lost).
But that’s what narcissists do… they rationalize their failures… live in alternate reality. They manipulate the truth… which I feel gives Vader so much depth as a character. Just my opinion… and I actually edited a version usind The Cutter’s line as well, as an alternative - check it out here https://vimeo.com/161839414
I think there are multiple ways to execute this scene without having to use the “Frankenstein breaking free” or the infamous ‘nooooooooo’ - my edits were just meant to show some possibilities given the material we have to work with. If they help or influence anyone’s edit, sounds great to me!