it is incomprehensible by default rather than intentionally.
I'm not sure of the intentionality of incomprehensibility of gobbledygook either, but its coining is credited to Maury Maverick, US Congressman from Texas, in 1944. He wrote a memo banning "gobbledygook language" and mock-threateaning, "anyone using the words activation or implementation will be shot."
Most people who do not speak a jargon, argot, cant, slang, or dialect usually insist that people who do, do so to confuse their audience and hide the topic of conversation behindsome kind of babble. Sometimes they're right, but sometimes not.
The intentionally incomprehensible candidates are usually called cant in English. There are plenty of examples around: e.g., Cockney rhyming slang, in Germany and environs, Rotwelsch (Gaunersprache 'cant', a mixture of German, Yiddish, Romany, etc.), in France Loucherbem (similar to Pig Latin, used by butchers, from boucher) and Verlan (from l'envers), and in Buenos Aires Lunfardo.
