I disagree with basically everything he said about Lisp: first of all, Common Lisp was the frontrunner for several decades, and can hardly be described as having the "smallest, cleanest core". Furthermore, Clojure has been reasonably successful in the past few years, and continues to increase in popularity. It doesn't have the commercial backing of C# or Java, nor does it have the head start of Python or Ruby, but it's getting there.