Why have any? Zero errors is trivially achievable by not writing code.

What if not writing code is an error in and of itself?

If it's worth doing it's already done

It's true, /bin/true.

Why try to improve anything when you could just keep the original implementation around for forever?

As they say, if it ain't broke, don't fix it

The evidence that C is broke is pretty overwhelming at this point.

For varying definitions of "not broke".

Thinking about my uncle, running Windows 97 in his company.

The El Camino was supposed to be an improvement. A combination between a car and a truck. It turns out it was not an improvement. It's better to just have a car or a truck. Cutting them in half and then weirdly stitching the two parts together creates a Frankenstein nightmare of bad engineering. Which even the best explanations on the planet can't fix.

^ If I can try to steel man this, it may be that having two different languages is simply worse than having one, even if the one language is non-optimal. Sure, if you were starting Linux today you wouldn't choose C, and hopefully Linux won't be the last operating system to ever exist, and the next one can use Rust. But Linux uses C, and no one is contemplating a full rewrite, so it's best to stick with C.

I have no idea if this is true, I am very much not a kernel developer.