As long as the kernel will be developed, there will be CVEs - even with Rust. So at what point the number is so high that we should drop Rust and move to formal verification? And even then, there will be CVEs... This whole argument is nonsense.
But I also do not agree that memory safety is of much higher importance than other issues. Memory safety is highly critical if you have a monopolistic walled garden spyware ecosystem - such as Android. Not that I do not want memory safety, but the people I know who got hacked, did not get hacked because of memory safety issue, but because of weak passwords or unpatched software. And at least the later problems gets harder with Rust...