Rust's library facilities are excellent for writing unsafe code with. Rust is very precise about which safety invariants must be upheld by which APIs, and does an excellent job documenting these, an excellent job at linting against improper usage of these APIs, and an excellent job leveraging the type system to reduce the need for unsafety in the first place. Writing unsafe Rust does indeed require its own degree of expertise compared to writing safe Rust, but fortunately it's trivial to just not write unsafe Rust; most Rust programmers only rarely have any cause to write unsafe code.