Not everyone has that option, thus we need to also improve C and C++.

As an example, while Microsoft slowly adopts Rust, it keeps putting out best practices and improved tooling, they aren't going to rewrite the whole Windows, XBox and Azure C++ code into Rust for the next couple of decades, or how long they would still matter on the market place.

Or Apple with they increased adoption of Swift, while still having to deliver C, C++, Objective-C and Objective-C++ stuff.

Or Google slowly adopting Rust, yet it still isn't officially supported on the NDK, or being the main language used on V8.