Rust has been rather monolithic. There is no such thing as a rust spec, just whatever the rust compiler does. This is a good first step to making it into a language people work in rather than just blog about.
A code-identical fork with a different name for trademark reasons is not going to make the Rust team write a spec. Look to the GCC Rust implementation for that.
Also, people already do work in Rust. It's in the Linux kernel right now.
Compiler behavior is the only thing that matters in any language, as per Hyrum's law. A spec is a useful tool for discussing and building a language, but don't confuse the map for the territory.
Also, people already do work in Rust. It's in the Linux kernel right now.