Rust is a much smaller language and stdlib than C++ (though still quite large). Rust makes an effort to make many things explicit that are implicit in C++, such as numeric type conversions. Rust's traits are conceptually simpler than classes, especially if you want multiple inheritance. Rust's templates/generics are much closer to the core language than C++'s template language.

And then there are all of the safety features of Rust; while there is a learning curve, it is much easier to learn the concepts of lifetimes and ownership when the compiler is helping to enforce proper usage.