My best guess is that they're trying to say that whatever www runs off looks at the host header, and that they'd need to do some additional work in either 301ing requests, or set up a reverse proxy. In either of these cases, yeah, the headline is a little sensationalist.

Based off the wording, it sounds like they're responding to "why can't I browse http://nasa.gov/x without the www?" rather than "why doesn't http://nasa.gov/x take me to the NASA website?", but as they're a government agency, it's quite possible that there's so much bureaucracy / cost involved that it legitimately isn't even worth it to add a url-redirect server somewhere.