None of this is a logical certainty of "X, therefore Y", it's just opinions. You can trivially add memory to a model by continuing to train it, we just don't do it because it's expensive, not because it can't be done.

Also, the phone book example is off the mark, because if I take a human who's never seen a phone and ask them to memorise the phone book, they would (or not), while not knowing what a phone number was for. Did you expect that a human would just come up on knowledge about phones entirely on their own, from nothing?