I guess Rust may seem more complex, if you know C++ well, but from the side it may not seem like it.

For example, C++ Core Guidelines [0] is longer than Rust Book. Core Guidelines is itself a great example of things one needs to keep in the head while writing C++ code.

Look at implementation of something as basic as optional<T> [1]. The amount of things one needs to know is so high most C++ developers would never attempt it.

[0]: https://github.com/isocpp/CppCoreGuidelines/blob/master/CppC...

[1]: https://github.com/akrzemi1/Optional/blob/master/optional.hp...