> And it's not because he's cranky or something, he was holding out for something worthy to possibly use instead of C.
Good point.
> Turned out to be Rust.
He was evaluating C++ in the 90's, you make it sound like he recently decided to write Rust instead of C. The reality is that Rust is allowed in limited ways into _some parts_ of the kernel codebase. Rust got so much further than C++ ever did, that is true.
Linus Torwalds famously said that subset is zero. You're not allowed to use C++ in Linux, a wise move.
Here's Google's: https://google.github.io/styleguide/cppguide.html Search for "do not use" and you'll find plenty of hits.