By that standard, no general-use programming language (even eg Python or Java) could ever be called "memory-safe". That level of pedantry is occasionally necessary, but not usually useful. In practice, I'd confidently wager the vast majority of Rust programmers have never encountered a soundness bug in the core language when not specifically hunting for one (I certainly haven't).
I'd wager the vast majority of Linux users have never encountered a memory safety issue with the Kernel. Memory safety issues are usually rare enough in world class C code that, by the time it reaches end-users, you have to actively go out of your way to exploit it.
Rust built its reputation around the idea that they can crush security bugs by making them impossible. They should be holding themselves to a higher standard than that "in practice" leeway. If a malicious actor can tease Rust into behaving in a way that contradicts its safety guarantees, then it could be serious.
Maybe your corporate policy is to configure Rust to allow zero unsafe code. Some crate you're depending on gets hijacked. It uses the cve-rs to crash your system even though Rust says it's 100% safe code.
The concept of safety is pretty different in a kernel and in a programming language. The kernel can be attacked directly with malicious calls, while it's the program created by the rust compiler that can be attacked (unless you envision Rust as a sandboxing technology, what it is absolutely not).
The safety in a programming language is mostly protecting the programmer against itself. The probability for a programmer to write this kind of code by mistake is close to zero, as opposed to UB in C or C++ that are pretty common. To make a vulnerable program with this kind of issue, the programmer would have to make them on purpose, what is unlikely unless for this kind of joke repository.
> I'd wager the vast majority of Linux users have never encountered a memory safety issue with the Kernel.
Yes, because they were caught in review and tests, or were patched in a bugfix release before being widely exploited. Rust catches safety issues during compilation, before you test or commit.
> Some crate you're depending on gets hijacked
Rust's safety is meant to protect against a certain class of programmer mistakes. You still need to audit your dependencies and sandbox untrusted code; the language designers have never claimed otherwise.