Not really, there are tools that can take C header files and spit out bindings. Rust also supports vararg C functions even though Rust itself doesn't support varargs. Writing safe Rust wrappers around these unsafe C bindings can sometimes be tedious, but this isn't worse than using C directly (which is inherently unsafe).
Yeah, my point was that thin shims are free, and "thick" safe shims take effort but as far as comparing with pure C is concerned you only need to compare the cost of thin shims. C doesn't have safety so the concept of a thick, safe shim is nonexistant.
