Edited to add: Oops, I forgot to follow the link and read it first! I would still treat it as a technical problem rather than "political correctness gone mad" though.

Not in my experience of using both Airport WiFi and dedicated internet terminals in some of the lounges I've used. There are many reasons why you might not be able to access internet address xxx.xxx.xxx.xxx from address yyy.yyy.yyy.yyy and a deliberate attempt to block access to a site is the least likely (unless you happen to be in one of the more despotic parts of the world).

Next time you are in such a lounge, just ask them to report the problem you are having to their technical support - their ISP may be having routing problems they don't know about.