The movie screams for being a mini-series, especially when some scenes feel rushed in spite of the already 3h30 runtime. I bet there is a 5-hours cut somewhere on Scorsese's shelves.
I enjoyed the minimalism of the movie, seldom using cinematic artifice to build up emotions, and depending on really great directing instead. Contrarily to recent long productions making heavy usage of soundtrack and editing whose result can sometimes feel like feature-length TikToks, Killers of the Flower Moon is all about restraint, and thoughtful dialogues, camera blocking, and acting.
The trio Leonardo DiCaprio, Robert De Niro, Lily Gladstone works incredibly well.