Glad I am not using FreeBSD

Modula 3 toolchain had been a recurring nightmare for maintainers. Having a critical (at the time) tool written in that was a painful mistake; the real solution was to switch away from CVS and be done with both cvsup and modula 3 support. An intermediate was "fuck that m3 shite, let's rewrite the parts of cvsup we really need in C, so the entire system wouldn't be a hostage of that horror" (csup). I suspect that phk point is not so much a literal requirement for rust-in-core-system advocates as a reminder of the last time when somebody decided that "it's such a nice language" was a sufficient argument for making the system depend on unstable toolchain.

They paid _hard_ for that mistake with m3. Granted, rust toolchain is nowhere near that horror (look it up yourself - it really could be used as an object lesson in how not to do language toolchains), but cvsup story must've left very painful scars.