- Much of the time, maybe even most of the time, memory corruption means security vulnerabilities. Logic bugs can be security bugs too, of course, but at least we can reason about them in local terms like "Is this particular part of the program security-sensitive?" Memory corruption doesn't admit the same kind of local reasoning. For any program that touches input from the internet, that's a huge deal.

- Just like C programmers can reach for Valgrind, Rust programmers can reach for design patterns that are more robust than Vec<T>. In this case, HashMap<u64, T> with an incrementing key is a very robust pattern. In practice (until you overflow that u64), that pattern catches 100% of your use-after-free-style mistakes. And I think a major advantage of Rust's approach here compared to Valgrind/ASan, is that it runs in production, so it works even if your test coverage isn't amazing.