All reasonable pain points. On the "Cargo fuckery" though, you might consider switching to an alternate build system like Bazel. Comes with its own set of issues (rustc isn't tied to Cargo, but the third party ecosystem definitely assumes it). But for embedded where you're cross compiling and working with C and C++ as well, I find it's a better solution than Cargo.

Rust is already used in production for embedded (although only here and there). Not all places are ready, but I don't believe it's a decade away anymore.

    > But I work in a space where C and C++ have been the only option for the last 30 years with absolutely no production-ready alternative.

What "space"? My guess: HFT or HPC.