Essentially he has no statistics to back his claims
I don't think you need statistics in a world where Java rules as a primary language for software development.
I've said here for years that Java is a great language for the 80% of average programmers because it tells you what's wrong most of the time, makes you do things right, and generally doesn't fall down unpredictably (J2EE FactoryFactoryFactories might be a different issue).
The top 10% can argue viscously about whether Python or Ruby or Haskell is the One True Language (shut up, LISP fanatics) - but in the meantime millions of developers are cranking out order inventory code in Java.
The top 1% of developers can deftly move back and forth among all of these, to suit the task.