Anakin becoming Vader is the new twist of the saga though. Because when you watch it in order, it happens in the middle and is literally the turning point of the saga. ESB is no longer in the middle like it was during the original trilogy. At the beginning of ROTS it seems Anakin has overcome his flaws (because he’s happy, mature, and has a good rapport with Obi-Wan during the rescue of the Chancellor)… only for him to succumb to his Achilles’ heal (not being able to let things go).

Trying to hide that Anakin is Vader is stupid and would damage the prequels. Like, you’re literally losing the best scenes of the prequels. The Knighting of Vader, the immolation scene, and Vader getting his suit give me goosebumps. If anything I’d be more in favor of hiding that Luke is Anakin’s son and framing it like he’s the Lars son or the son of some other Jedi Master, maybe even Obi-Wan, but even that is dumb.

I’d argue that knowing that Luke and Leia are Vader’s children but none of them know adds TENSION, you’re wondering when they’ll learn the truth and what the consequences of that will be. How will Luke react when he finds out Vader is his father, and that the man he thought he could trust most lied to him? Because unlike what JJ Abrams thinks, surprises are not the most important thing in storytelling (or the only important thing, for that matter).

Also regarding Yoda I’d argue that it’d initially make people wonder “Why’s Yoda acting like this… this is weird”.