I don’t think “best” means anything objective, and “systems” is also pretty ambiguous (it describes a class, but that can be interpreted extremely broadly). Rust is still fresh, and people like new things. I think it has legs, but practically I think things need the test of time and many critical projects before you can really assert that it’s the “best”, if at all.
In terms of playing with hardware: did you want to learn rust, or understand low-level programming? I think rust will help you make a more robust, correct application (with a lot of time and effort understanding rust itself), while C won’t do much to help you but you’ll be able to be right next to the hardware. Personally, I think if your goal is to understand how hardware works, I’d use C. (But if you want to learn rust, use rust.)
In terms of playing with hardware: did you want to learn rust, or understand low-level programming? I think rust will help you make a more robust, correct application (with a lot of time and effort understanding rust itself), while C won’t do much to help you but you’ll be able to be right next to the hardware. Personally, I think if your goal is to understand how hardware works, I’d use C. (But if you want to learn rust, use rust.)