I haven’t don’t much programming in Rust yet, but just based on the syntax and apparent complexity (at least it looks quite complex to an outsider like me) it always seemed more like “C++ but better” rather than “C but better”.
I haven't used Zig myself but I think it could have its place. IMO Rust has moved too far away from C to be something many existing users will move to (and using both in the same project is messy), but Zig seems to integrate well enough that it might.
I’m not saying Rust is better - I prefer c/cpp myself. I’m just saying that if someone is going to move away from c to a new language, it’s overwhelmingly more likely to be Rust.