It's now apparent from this transcript that Gosling's error was over-generalization: he's lumping "all of these dynamic languages" together and making incredibly un-provable statements about them as a whole. That's a good way to get your comments eternalized by angry blog-rebuttals for weeks on end, but it's not a good way to evangelize your language or tout its strengths.
In addition to shedding light on these mysterious comments by Gosling, I'm happy to see this transcript for another reason. It contains an excerpt that really sums up why I was glad to get out of Java and into Ruby (here I go, taking things out of context!): "On the one hand we really need simplicity, and on the other hand we really need power. And those are evil twin brothers of each other." There it is. The archetypal tenet of the Java philosophy: power necessitates complexity! Yuck! I couldn't disagree more with that philosophy. After having worked in Java for the past few years before coming to ruby, I can attest to how pervasive this philosophy is in the language itself. It makes me sad, though, to think of all those people still living in the Java box, dreaming up good ideas that they're throwing out because they're too simple to be powerful... Come to ruby, where simple is beautiful!