Note that this is marketing copy aimed at Mathematica users, mainly scientists and mathematicians, most of whom probably don't know what LISP or Haskell are.
I think that's part of it. It's also aimed at non-hackers who took a look at Clojure once and said 'yuck'. And managers who are being 'groomed' not to totally freak out when someone on their team says "can we use the Wolfram Language on such and such a project?".
