Since this is a from-scratch implementation, there's not much support from the language side to begin with. Except for some build system details that may have been made less annoying, I don't think much has changed.
However rust versions everything, so even if you have a new compiler that removed support for something, you can still pull the old toolchains and build legacy codebases (like this one).
My Rust OS not only pins the edition (which is the default anyway with `cargo init`) but also uses a toolchain file to pin the date of the nightly build I want contributors to build with.
Rust tooling is really fantastic in this regard.
I chuckled a little, after all, GCC isn't versioned and there's no companies out there still using GCC 4 or whatever kind of suffering they prefer.