I don't think college essays, etc would contain anything novel. Future techniques could smoothly interpolate better creating ever-anew wordmud.
1) Based on how pre-verbal children learn, one nitpick is that I strongly suspect we need to give AI touch and a sense of space in order to truly understand quantity, causality, object permanence, etc.
2) Something that is not a nitpick: even a superhuman multimodal AI wouldn't have direct access to human emotions, sexuality, ideas of natural beauty, etc. I don't think humans have run out of interesting things to say about these ideas.
(In particular, I don't think a superhuman AI is capable of understanding music unless it is directly emulating the biological processes by which humans understand music. The issue is not "logical" - melodies don't actually make sense analytically.)
That's quite a proposition.