option 1) S was created at AT&T, the home of UNIX and C. Imagine if statistical functionality had been made a standard part of C rather than developing a new language. While C is maybe not that popular anymore, current languages like Java and C# inherit from it, and we would have a world in which statistical functions were taken as given as part of the default libraries of any language.
option 2) Use another standard language like LISP. This actually was done in the excellent LISP-STAT system. Unfortunately it came out at kind of the wrong time for LISP. These days LISP is kind of undergoing a renaissance with Clojure, Racket, LFE, etc., but in the 1990s it was more associated with the failed AI efforts of the symbolic school and LISP was just seen as this weird thing with lots of parentheses by many people.
The thing is I use R every day. But like everybody else, I bury it under lots of add ons like Hadley's and others to make it palatable by hiding as much of the absurd R syntax as possible. That's like dumping ketchup on foul tasting food. Is this really what we want to do?