Overloading doesn't scale when there are tons of ways of making a `String`. I don't see why `Into<String>` is "out of your way"; it's actually less verbose than overloading.
Into<String> is "out of your way" compared to having a String parameter in Rust. (Thus the person writing the code is expressly asking for the interface to allow implicit copying.) It is not being compared to C++ overloading. (The point is, this is more "out of your way" than you have to go in C++, where using an unoverloaded argument type of std::string will get you copying with opportunistic moving, and where a const std::string& will get you copying somewhere on the inside of the function. Thus Rust protects you from accidental expensive copies.)
