You can’t improve and break silence without discussing and making changes. The existing maintainers won’t live forever, having Rust in the Kernel is a bet on the future. Linus wouldn’t have adopted and accepted Rust, if he wasn’t thinking its worth it. And looks like it was already worth it.
If we can believe random strangers in the internet, then Linus uses a self maintained lighter version of Emacs, or has. Looks like Linus is an Emacs guy.