This could be used within https://bootstrappable.org/projects.html to make bootstrappability of rust incredibly much easier other than the previous route of OCaml and other things.

I know some folks within the bootstrappable OS projects community are on Hackernews and I hope that they could take a look at this. I feel as if this project could drastically shrink down the efforts needed to get a working rust compiler in a bootstrappable manner.

mrustc (a handwritten Rust compiler in C++) is already used for that in Guix and likely other distros: https://guix.gnu.org/blog/2018/bootstrapping-rust/ This would have other benefits though, as it's both a second bootstrapping path and could potentially compile Rust programs for platforms not supported by LLVM

Not really. This C code is more like a binary and compiler artifact than a source code. So it won't match the standards of bootstrap.