The point of this LPC session was how to incrementally introduce Rust in the existing Linux kernel, with all its existing drivers and syscalls and similar. A rewrite would indeed be a daunting and problematic proposition.

There are kernels written in Rust, such as Redox, but those are separate projects, and that's not what this conference session or article are talking about.

Standing reminder: the Rust project is not a fan of rabid Rust over-evangelism (e.g. "Rewrite It In Rust", "Rust Evangelism Strike Force"), and sees it as damaging and unhelpful. We discourage that kind of thing wherever we see it. We're much more in favor of a measured, cautious approach.