Someone already mentioned that Chewbacca could be somewhat understood in the Star Wars universe. That's an objective fact.
Is it? In the onscreen version of that universe, Chewbacca doesn't really deliver any information to his fellow adventurers through his growls - except when pointing at a warning light on the Falcon
's control panel at the same time, or suggestively waving a gun, etc. Sure, the heroes "answer" as if they understood what Chewbacca said, but the various handlers of Lassie did that a lot, too. Doesn't mean there'd be intelligence at both ends of the conversation.
The Calamarain appeared just plain alien, plus just a tad hostile. The Breen appeared secretive, and very hostile. Surely the latter would put more effort to thwarting any translation attempts...
Seriously? In WW2, as soon as the Germans figured out that the British could understand German, did they suddenly change what German was? Codes and secret communications, yes, you are right. But the basic language, no.
Yes, seriously. What could Germans possibly have to do with this? They didn't have Universal Translators.