"Luke proved that attachment was a good thing and that the Jedi were all dogmatic and wrong"
is a take that fundamentally misunderstands both Luke as a character and the entire point behind Star Wars and the Jedi religion.
Luke didn't act out of attachment. If he did he would have killed Palpatine and Vader in a desperate attempt to save his friends.
Let's actually compare this to mister attachment aka Anakin, shall we.
If Anakin was in a position where some guy (for example Dooku) was responsible for Padmé, Obi-Wan, Ahsoka, Rex etc. being in current life threatening danger, he would have killed that man and anyone who stood in his way. If there was another guy claiming to be his father that might have thrown him off for a bit but in pure rage and terror of what might happen to the people he loves he would have 10000% killed him, father or not (he literally tries to kill his surrogate father / brother out of attachment and greed and later succeeds IN THE MOVIES).
Luke however chooses AGAINST acting out of attachment. He doesn't let his fear for his loved ones control him. The literal moment he crashes out and eventually almost kills Vader is when Vader mentions Leia. His attachment to her led him to react with rage in a desperate attempt to protect her but then he realizes that that's WRONG. That he's playing into Palpatine's hands and giving himself over to the dark side, so he stops. He chooses not to become what Anakin let himself be turned into.
Luke's motivation for saving Vader is not attachment - it's compassion.
Attachment is to act on behalf of yourself. Attachment is choosing your own feelings over what the people you love would want. Attachment is sacrificing everything your wife stood for, choking her to unconsciousness because she doesn't react the way you want her to and trying to kill your own brother out of greed and jealousy. Attachment is selfish love - love that is about YOU and not the people around you.
Compassion is SELFESS love. Compassion is choosing others over yourself. Compassion is valuing the ideals and wants of the people you love - not just wanting to keep them by your side at all cost. Compassion is tossing away your lightsaber and letting yourself get tortured and almost killed because you REFUSE to act out of attachment and let anyone be hurt but yourself. Compassion is also to sacrifice yourself to save your child even though it gains you neither a better future nor him staying in your life.
Luke's compassion motivated Anakin to act out of compassion as well. That's what the movie is about, guys.














