I think it's not that it has historically been overvalued, so much as the valuation wired into us hasn't fully accounted for the consequences of mass reproduction.

Before the printing press, a poet was valued and valuable; today, the feeling of valuation remains, but instead of each village of 160 looking after their own poets and bards, it's a power-law distribution where Taylor Swift and J. K. Rowling are worth hundreds of millions to billions while the person at the end of the top 100 best-seller lists absolutely needs a second job.