You are missing something. For a piece of Rust software to run in any widely used computing environment, it is required to interface with a large body of non-Rust software via a non-typechecked ABI. Moreover, the Rust standard library itself contains many, many instances of the unsafe keyword. The benefits of Rust safety do not come from building a hermetically isolated tower of pure safe Rust code from the ground up, and those benefits do not become null and void the moment you include one C library used via FFI.

Rust safety is about being able to take an unsafe component, encapsulate its implementation details, and encode sound usage patterns for that component in a public API which can then be statically checked by the compiler. This allows the difficult problem of determining whether an entire codebase is sound, memory-safe, and free of undefined behavior to be factored into many smaller, more tractable problems of verifying that individual components are sound given their APIs. You can even do this with wrappers and bindings to C libraries, and there are many examples of this in the Rust ecosystem.

Wins are often incremental. It's much better to start with the potential of guaranteed safety, sidestepped by a manual (opt-in) sacrifice of it in favor of getting something working, and slowly chipping away at the unsafety over time; than to start with the dispensation of safety as an institution altogether (C/C++) and hope that someday you can work your way to safety.

Put another way, as a developer, I'd much rather be part of a project using a language that is safe by default, which opts in to the unsafety it needs yet which hopes to someday simply remove all the `unsafe` keywords, than one that hopes to stumble its way to safety through relentless trial and error, testing, bug reports, debugging, etc. and has no actual measure of its level of safety.

On top of that, if you only use, say 10% of one of those libraries, you can easily wrap the 10% of that library in a safe fashion instead of waiting for 100% of the library to have its own safe wrapper.