That's not the problem. It's naive inexperienced developers using the tools. Most developers have to maintain code they didn't write themselves. One can learn all the C++ best practices in the world, but it won't protect you from other people. That's why languages with strong restrictions and constraints that force safety and correctness are needed. With such languages, naive inexperienced developers won't be able get anything to compile. We won't have to deal with their mistakes as they'll never be able to ship them. Any experienced developer would surely want this.
A rewrite is not pointless if you are rewriting into a language with additional guarantees. You are checking for and proving the absence of certain classes of software flaws by doing so.