But the core guidelines are optional -- which means that you&#x27;ll still have the entirety of C&#x2F;C++ footgun hell to watch out for, and decades of outdated teaching and learning materials. And very large codebases which could not be easily ported to a compiler that enforced those guideines.<p>I will be happy if Rust&#x27;s main impact on history will have been to showcase how to get those safety features into a practical language, and by extension improvements to C++, but I still think that the steps C++ is taking seem a lot less safe than what Rust has achieved by completely ignoring backward compatibility with C++98. See, for example, the compiler-enforced concurrency safety that Rust provides. I haven&#x27;t read the core guidelines recently or in depth, but IIRC that&#x27;s not a stated goal of the project.