Why isn't operator overloading for pointers allowed to work?

Question

As per the comment under this answer, references were introduced primarily to support operator overloading which quotes Bjarne Stroustrup:

References

Answer 1

Operators can't be overloaded when both types involved are built-in types (like int, float or any kind of pointer). You can overload operator for one class and one primitive type (or you can just use type conversion). For example you can add std::string and const char *.