The only person Anakin/Vader ever blames in absolutely everything (even things clearly outside of his control) is himself
Even when he's angry at the order for not recognizing him as a viable member - he's angry at the order for like 5 seconds, as a knee jerk reaction to being told "you don't belong" again, and then angry at himself for never being good enough for 20 years, because he always retracts into "no, it's me who's the problem" mindset
Really wish there were more depictions of Vader not as some angry vengeful thing that hates everything and blames everyone, but a tired, middle-aged man, who's just beyond his capacity to care anymore
Of course he's still angry, he's hurt, he's deeply traumatized by just about everything in his life, but all he probably feels for the jedi and Obi-Wan after 20 years is apathetic disappointment, reminiscing on what could've been, and what wasn't
Apathy as Vader's general mood hits harder than anger, because he's not just a man who has nothing to lose - he's a man who _doesn't care_ if he loses anything
He doesn't rush into a fight with a need to kill, he doesn't enjoy or savor it, he's not bloodthirsty or needlessly cruel
He's efficient and endlessly bored with the tedium of it all
And that's much worse
Because the only thing that moved this man for 20 years is pure need to move, with no goal or reason behind it, movement for the same of movement, driven only by need to survive, because at this point surviving through it all is the only thing he's good for
Pushing through all possible limits and surviving out of duty, because if he dies - he knows he can't be replaced, or at least not easily replaced, and then it all was for nothing
He has to survive, not because he wants to live, but because there has to be a point to it all, eventually
Man's only motivation in life is sunk cost fallacy, and he's ready to drop the entire galaxy together with himself into this endless pit, if it means that things will finally make sense
Right up until the point when he finds the only person that's actually worth living for, and doing things for, and it's the only thing that animates him to the point of trying to shake the stagnation off
That's why Luke is so uniquely important, imo
Obi-Wan or Ahsoka or even Padme herself, anyone from Anakin's old life could never have this effect, because they're already behind, they're down in the bottom, in the heap of endless disappointment and things that didn't work out, they're in the discard pile, and Luke is not
Luke is something that was supposed to be, but never was, and now it has a chance to be again
It's an opportunity yanked away right from Anakin's fingers, only to be returned back 20 years later, in the moment when it was needed most
And the fact that it's not just anyone, but specifically a child, his child, who called him "father" mere minutes after Vader chopped his goddamn hand off, who was insisting that Vader is good _while being led to an execution by him_, if not worse
That's everything
Because Vader, despite being selfish, to some capacity, lacks ability to do things for himself
He could never get better for himself, he could never actually defeat Palpatine for himself
But for the son - son is worth everything, son _is_ everything and deserves only the best as a result
There's something cathartic in watching Vader finally kill Palpatine
Because it's not something coming from Vader himself, it's not his own hurt or his own anger, it's not about Vader at all in the moment
And that's why it's cathartic
Something finally derails him from endless "it's my own fault" and compliance with all that's happening, something finally makes him act, defend and fight back instead of lowering his head and taking it in
Luke is a proxy for Vader's feeling of resent towards the cruel, unjust, unfair system that keeps hurting and breaking him
He lacks the capacity of being angry for himself, he doesn't deserve to be protected from it
But Luke does, because Luke deserves everything