[Dho Chladach]

The root cause is actually fairly simple; Maesda (and Lesser Wood, by extension) was ruled over by a pair of supreme deities; a creator, and a destroyer. Then deicide happened, resulting in the destruction of the creator. Without her, the world was thrown into an irreparable state of decay.

Not that Braeg would listen if Inari explained. He's too busy curling onto the ground, audibly weeping.