Well, yes and no.

On the one hand unsafe Rust is roughly similar to C[1], and unsafe Rust is a subset of Rust. But unsafe Rust is not the most widely used subset of Rust, stable Rust is ! And stable Rust is arguably way easier to understand and work with than C. And you can write fairly complicated software without writing a single line of unsafe code.

[1]: even though, the more expressive syntax and type system of Rust makes a lot of things less error-prone in Rust, like pattern matching or Result<> for error handling instead of switch and goto.