Combined with the large number of vulnerabilities in mature, well-designed programs implemented by skilled programmers. The mythical programmer that can use C/C++ without bugs doesn't exist.
The mythical programmer that can use Rust without bugs doesn’t exist either. I deal with higher level languages than rust and we’re capable of writing just as dangerous stuff through implementation errors.
While bugs like logic errors clearly can exist in all languages, those that do things like memory management/enforce memory safety for the programmer eliminate whole classes of bugs.
No language/tool/etc will stop all programmer mistakes, but they can definitely stop some.