This is a bigger point than it might sound. While "learning C" doesn't sound like a huge task, learning C well enough not to create disasters when working on a kernel, is a huge undertaking and requires a lot of experience.

Being able to do kernel development in Rust should lower the entry barier into kernel a lot. Because it has more high level constructs and especially for all the safety Rust brings. Any competent programmer should be much more comfortable to start kernel dev with Rust than with C.