Many point out that it invalidates Anakin’s redemption in Return of the Jedi, but it doesn’t, really. He only killed Palpatine to save Luke, his last remaining loved one, not necessarily to save the galaxy, topple the Empire or fulfill the prophecy as the Chosen One — his destiny as the Chosen One was merely there in the prequels to put in some additional weight to his fall.

Anakin could’ve thrown Palpatine into a ball pit and his sacrifice would still retain the same meaning — he did it to save his son. Luke dying ten minutes afterwards from some kind of disease or cancer would’ve made Anakin’s sacrifice all for nothing. His motivations were so obvious, just by watching the scene alone in Return of the Jedi.

I’ve changed my mind.

Anakin saving Luke isn’t the point.

I mean, personal motivation for bringing balance to the Force isn’t really that important, just that it’s done. Fate/destiny often tends to end up being fulfilled unintentionally, or even when actively trying to avoid it. That’s a common theme throughout the ages in literature.

The prophecy fulfills regardless of the reason Anakin kills Palpatine.