When I said that people know how they end I didn’t mean a single thing but everything in it. When I saw a death star in the original trilogy, I figured it out myself it was going to blow up in the end f the movie - it goes without saying in this genre. And it goes up with a huge explosion. And both times.
It’s more like things besides that -the only thing that kept the characters alive was that you didn’t get even a hint if Leia was going to choose Luke or Han. After you know that Luke and Leia are brother and sister, the characters have nothing anymore. You can show that once they had parents - ok, I kind of expected that.
Also, if you tell a story about a normal kid becoming Darth Vader you have a chance. Show this evil Darth Vader in the beginning then go back showing an ordinary boy and you’re just giving the wiever less awesome.
And finally the arc of drama whether it is easy to grasp or not. If you start blowing up death stars, you need to have something more awesome in store to make more movies. Blowing up more death stars all the time is just boring but equivally boring is to explode just normal things, people, robots, ships etc. I think this is equivalent to making a movie about Apollo 13 and then expect your prequel Apollo 12 to be a blockbuster.