We need algebraic effects in more languages, this solves the function coloring problem. OCaml 5 has them and it seems to be doing quite well, combine that with the semantics of the borrow checker in the form of OxCaml and we might just have an ideal language. I'd like to see algebraic effects in Rust as well but sadly it seems their keyword generics initiative is languishing.

Related, one of the former React maintainers wrote a primer on algebraic effects that's a good read: https://overreacted.io/algebraic-effects-for-the-rest-of-us/

I don't think effects alone solve function coloring problem, in worst case they make it worse because every library can have its own colors