Not Even Ridley Scott Has Interesting Alien Stories To Tell
There's a certain beauty to the one-two punch that is Alien and Aliens. Alien is a cool slow-burn thriller that suddenly leaps to monster movie territory when the titular extraterrestrial turns John Hurt's chest into a bowl of soup. Aliens is an action/horror masterpiece that relishes in delivering one badass sequence after another. They both take the same concept ("Oh shit! Aliens!") and deliver in entirely different ways.
Since then, the results have been ... mixed. And that's putting it in the best possible terms. Alien 3 has become well-known for being a disaster behind the scenes, Resurrection is a mess, and the two Alien vs. Predator films are best left in the "4 USED DVDS FOR $20" pile in haunted Blockbusters around the globe. Side note: No movie monster is actually improved by adding more and more layers of complicated lore and backstory.
At some point, it was decided that what was missing was the original director, so they went back to Ridley Scott, the man behind the first film. But 2010 Ridley Scott is not the same director as 1979 Ridley Scott, and I imagine even Ridley Scott knew this, as he didn't want to direct the prequel Prometheus in the first place. But when Fox threatened to cancel the project, he attached himself, making it clear that it would be mostly new ideas. A few months later, though, he resigned to basically saying, "OK yeah, the last third of it will be old Alien ideas, but they'll only be ideas from MY Alien movie." You may recognize that he did this again with the sequel to Prometheus, Alien: Covenant, originally stating that he was done with xenomorphs before making a sharp U-turn and packing the movie with them.