I'm really ambivalent about the prospect of a Knives Out sequel, because I definitely want Rian Johnson to do another movie like that, but I think what I really mean by that is "the same sort of thing but with an unrelated plot and completely new characters that it makes me love as much as Knives Out made me love its characters", because Knives Out is a carefully designed device and I don't think you can just take some of the pieces out and build a new device around them and have it work as well.

I'm particularly unenthused about the idea of another detective mystery story starring Benoit Blanc, because I think a lot of the things that make Knives Out work so well as a mystery story are specific to the story of Marta and the Thrombeys (like the fact that Harlan Thrombey is a mystery writer himself, and the way that influences how various characters react to things; or the way that Marta and Blanc spend most of the movie figuring out where they stand with each other). And if Johnson reuses those elements in a sequel, people will say he's repeating himself, and they'll be right.

I like the idea of switching up the genre and Doing Courtroom Drama the way the first movie Does Murder Mystery; that follows from the plot, as you say, and it opens up a way to bring in different elements. But obviously "the sequel is a completely different genre" is not something studios tend to go for.