"collaborative" "Rust" "code editor" "CRDTs" is very reminiscent of Xi Editor by @raphlinus which shared all of these traits. Xi was abandoned with the conclusion that CRDTs aren't suitable as a basis for text editing interactions, or at least that implementation wasn't.
Is Zed related to Xi in history or as inspiration? Why are you confident that Zed will be able to overcome the issues that blocked Xi's advancement?