Google has published direct evidence of Rust improving memory safety in practice: https://security.googleblog.com/2022/12/memory-safe-language...

> To date, there have been zero memory safety vulnerabilities discovered in Android’s Rust code.

That was 2022. I am aware of at least one security bug in their Rust code, but it wasn't a memory safety issue. I'll be interested to see what they say when they post updated numbers.