The correct comparison to someone asking for first-party access to a C syscall is to the first-party crate that provides direct bindings to C syscalls. If you're willing to go further afield to third-party crates, you might as well skip rustix's "POSIX-ish" APIs (to quote their documentation) and go directly to the openat crate, which provides a Rust-style API.

If I have to use unsafe just to open a file, I might as well use C. While Rustix is a happy middle that is usually enough and more popular than the open at crate, libc is in the same family as the "*-sys" crate and, generally speaking, it is not intended for direct use outside other FFI crates.