The argument could be made that rewriting in general can make a codebase more robust, regardless of the language. But that's not what the article does; it makes it specifically about memory safety:

> That’s how I feel when I see these companies claim that rewriting their C++ codebases in Rust has made them more memory safe. It’s not because of Rust, it’s because they took the time to rethink and redesign...

If they got the program to work at all in Rust, it would be memory-safe. You can't claim that writing in a memory-safe language is a "minor" factor in why you get memory safety. That could never be proven or disproven.