I think that is the key.  Your understanding of languages is fundamentally different from mine since I was not born deaf.  We are two different types of machines but we both started off with the same hardware.  The network in your brain established in a very different way from mine and that's got to be an amazingly cool difference.  But, at some fundamental level, you are as mysterious to me as I must be to you in regards to languages, and both of us are  mystified by the AI's understanding.
In a real sense everyone is a blackbox to everyone else.  How you process concepts like "pronunciation" (if you do at all) or subtleties of "tonal languages" (like Chinese) is a complete mystery to me.  And presumably I am to you at some level.
That's my point about AI.  That it walks like a duck, quacks like a duck, has feathers like a duck, but I'm constantly being told it is not a "real duck".  I think I disagree.