C is a language that doesn't come with many guarantees. I personally like to think of C as a 'higher-level assembler', targeting a virtual machine. I've been led to believe that this figurative description of the language was more common in the past than it is today. I find it a helpful description since it offers an explanation for many of C's design choices. Such as it's weak types and use of pointers. If I'm correct it's also an accurate description of the language's original aims in system development.
Also, Rust isn't the only systems programming language with a focus on safety. Ada has been around for some time now and is a much more mature language and arguably more suited for the job. It has a demonstrable track record of successful use in safety-critical software. Rust is definitely more 'C-like' than Ada, which might make it preferable to many.