Didn't all of those other villains initially die (some prior to the events of the main cinematic story) specifically and intentionally so that their return could serve the story *of the main heroes* and the end of their journey? That purposefulness is a far cry from how and why Palpatine was brought back, right?
Wasn't Sauron's return what gave purpose to Frodo's journey with the ring? Wasn't his ultimate death meant to elevate the central character's purpose in the whole trilogy?
And wasn't Voldemort similarly "returned" in order for the main character *of all eight films* to be able to fulfill his journey and destiny?
As for Thanos, wasn't his "return" (within the same film) similarly meant to provide the longstanding MCU heroes (Iron Man being the first) with a triumphant conclusion to their prolonged journey against him?
Palpatine's return, on the other hand, did nothing to elevate the central character of the Skywalker Saga. Whether you believe that to be Luke or Anakin, it sure as **** wasn't supposed to be Rey. So, Palpatine's return actually undermines the collective effort of Luke and Anakin in ROTJ by having no permanence attached to it. Even if they didn't secure everlasting galactic peace (a naive and silly expectation anyway), they accomplished the end of the Sith - or at least Palpatine. But not anymore.
Palpatine was brought back to serve which characters? What Skywalker Saga arcs did it serve?
The answer to that question, when compared to the return of other movie villains, is the reason why people like me object to his return in SW.
In horror movie sequels, the villains are the main characters; and their return is the focus, while the protagonists are interchangeable. With Indy, the movies never suggested that he defeated the Nazis.
And Skynet (and its terminators) were there each time to serve and extend the story of John and/or Sarah Connor.
Palpatine was in GL's saga to be defeated by Anakin and Luke. That was his purpose. He served that purpose. Bringing him back *for a new hero to defeat* undermines that purpose for some of us. If he was brought back to serve some unresolved character story for Luke and/or Anakin, it wouldn't be as objectionable.
Do you at least understand what I'm saying here? Sometimes it seems like you give no credence to any objection of Palpatine's return. It kinda blows my mind.