The other options: Scarlett Johansson
Really, no one has a chance in hell at winning this other than Dern. However, the Oscars love Johansson this year. She's a double nominee for both Jojo Rabbit and Marriage Story. Here, she plays the mother of the protagonist, secretly resisting the Nazis while trying to make sure her son does not become a zealot. She's one of the best things about the movie.
My biggest failure in the first draft of this post was underestimating the potential love for the performances in Bombshell, Jay Roach's retelling of Roger Ailes ouster at Fox News over charges of sexual harassment. Robbie is one of the few people in the movie not playing a real person. Hers is composite character representing the many upstarts at the company who were victimized by Ailes. I always thought Robbie had a shot at this category, I just initially guessed it was for Sharon Tate in Once Upon a Time...in Hollywood and not this.
Even in a cast featuring Dern, Meryl Streep, and Saoirse Ronan. Florence Pugh makes the strongest impression in Greta Gerwig's Little Women as Amy. Gerwig's structure offers Pugh the biggest showcase as her character evolves from a childish brat into a young woman conscious of the limits society places on her. (Pugh's desperate, terrifying work in Midsommar is another reason to anoint her as the next thing.)
Arguably, the biggest surprise here, other than Lopez's shut out, is Kathy Bates making it in for Clint Eastwood's Richard Jewell wherein she plays the mother of the wrongly accused protagonist. Adam Sandler, despite being snubbed himself, is happy about her nomination.