Yes he does see the benefits to dynamic languages, but wonders why you would use one considering that those benefits are present in "good" static languages.

Good static languages have pattern matching and sum types, which gives you the ability to work with tagged data in a syntactically clean way. Dynamic languages just tag all the data. OP's point: are you aware of this? You could be as dynamic and as static as you want in a language like ML or Haskell.