Rust also provides guarantees that goe beyond mere memory safety. You get data-race safety as well, which avoids certain kinds of concurrency issues. You also get type-safety which is a step up when it comes to parsing untrusted input, at least compared to C for example. If untrusted inout can be parsed into your expected type system, it's more likely to not cause harm by confusing the program about what's in the variables. Rust doesn't straight up eliminate all source of error, but it makes major strides forward in areas that go beying mere memory safety.