Considering that C doesn't have any good facilities for polymorphism, it's going to continue to be the argument of any language that succeeds C. Unless, that is, that successor language also doesn't have any good facilities for polymorphism, in which case we have Go as a fascinating real-world study in how people will incessantly demand them and deride the language for lacking them (which is saying something, considering that interface{} in Go is already better than pretty much anything one would hack up in C via void pointers or macros).