Doomed by the Shadow…
The Swollen Shadow’s magic is such, that anyone transported to its demi-plane, will always first arrive in the somber and hazy Umbral Fens, which surround the City of Shadow. After some searching one may find the Brittle Road, which leads through the shadow-choked swamps, to the City proper.
A Renaissance dawns. A School of Art emerges.
As population increases, animal souls are promoted to human before they are spiritually advanced enough in terms of impulse control, etc.: this shouldn't have happened, but karmic progression is automatic, after all--it's a force of nature. But the 'animalization' of humankind bodes ill for civilization.
No doubt the same goes for elves, dwarves, and so on.