Arc seems to embody the idea that "Language design is library design, and vice-versa", but how can we tell where the boundry is?

When I look at something like

  (defop said req
    (aform [w/link (pr "you said: " (arg _ "foo"))
           (pr "click here")]
      (input "foo") 
      (submit)))

what I see is more or less ordinary lisp that uses a library to solve an issue with applications that rely on http. I'm sure plenty of us could do the equivalent with the appropriate Python/Perl/Php/Ruby library, but then the obvious criticism would be that you're not really comparing lanugages. You would be comparing libraries.

Plenty of examples over here: http://arclanguage.com/item?id=722

Is it really the case that when you boil it down, Arc (language+libraries) is about making small web programs? If not, why this challenge and if so I suspect it won't live up to the 100-year idea.