> To my mind, letting Abrams double-down on swerving back to his plot in episode 9 was their biggest management sin when it comes to creating a coherent plot arc.
Abrams was an Executive Producer on Ep 8 still and was supposedly in the room for all of the plot development. He personally could have avoided most of that swerve had he been paying attention. Admittedly, he thought at the time it was Trevorrow's problem because Disney didn't fire Trevorrow from Ep 9 until the "last minute", but there's a lot of interesting questions left about what Abrams even thought the "resolution" could possibly be even with Trevorrow at the helm. He was still an Executive Producer in a role that should have been preparing for the trilogy as a whole to succeed.
It takes a village to make a movie and all that, and I'm not personally blaming Abrams, though it sounds like it, I think Disney management should have been more involved too. The whole Trevorrow thing reeks of Disney management failure and bad contract planning. (Between that and the shenanigans with Lord/Miller over Solo…)
I think Abrams made the best movie for Ep 9 that he could have given the time, budget, and resources he had to meet a "set in stone" holiday release date. I think he did the best he could with what Johnson left him, and honestly I don't think anyone could have resolved Johnson's plot twists well and still have felt like Star Wars. He had good ideas in absentia, but they weren't "Star Wars".
(Admittedly, I thought Ep 8 was the entire wrong genre for Star Wars: it was a Vietnam War movie in a franchise built around World War 2 metaphors/aesthetics. I also had a big issue with the "Three Billboards problem" of Poe in Ep 8. In my eyes he's unreedemably the villain of the film, and the character is entirely broken beyond repair in Ep 8. But also, admittedly, I haven't liked any of Rian Johnson's films that I've watched [inc. Knives Out; and I especially hated Looper].)