Just want to point out that not that long ago redox-os (the microkernel OS in Rust) asked people to test it.

People were able to kernel panic it, get privilege escalations, and DDoS it. In short, it had the same same issues a C based kernel would get.

It's true that it's still heavily in development and doesn't offer any guarantees whatsoever, but I think that it should be pointed out that just because your language is good, doesn't mean that your end result will be good (and vice-versa, C based kernels like l4 and C based projects like SQLite have been formally verified (at least SQLite was verified after compilation, so they check for undefined language constructs.))