I've implemented a basic ML variant before, and maybe half a dozen different lisps. Rust is only BARELY functional. A C++ guy ought to know better!
Believe me, I'm not interested in Rust for Rust's sake. If there were a GNU implementation, I could see writing code generators for Rust a little less cumbersome than trying to target C or LLVM IR or Wasm.
Realistically, I see Zig winning the fight that Rust is trying to fight, and C++'s headaches being replaced with Rust's headaches.