Who is more correct, the child or the adult? If you suggest the child, then what do you say to the adult who objects on the grounds of the meaning of the sounds uttered? The adult would say that though the sounds are pleasant to the ear, they are not good to the mind. Thus, rather than affirming the child's vision, they would reject the pleasant sounds with poor meaning in favor of higher quality ones which are as equal in their harmonic value as with the greater quality in their meaning.
As for the infinite regress, that only proves the value of knowledge all the greater, for if we can expand our knowledge on the origins of something continually, so too can our appreciate of the thing grow in proportion. This only leads to a richer and deeper appreciation for life. In this way I can reread or rewatch a show in time and see more and know more than in my first experience, and so grows my appreciation for the details that I missed the first time. And this may only occur if the subject at hand is of good quality in the first place, for else when we descend further into the details and meaning we would be dissapointed at its lack. But that which is rich in meaning lacks none and may reveal itself new with every experience. This is why knowledge of the good is required, and why AI and lackluster artists may only produce pleasant sounds.