but Kunlun is the only actual god left, isn't he?

And he's only left in so far as he still exists but in a mortal form. (But huh, I hadn't put that together, that all the original gods are dead now. So "the Heavens" persist, and all the Netherworld bureaucracy persists (or has established itself over time?), but everything else is kind of static because the powerful being who can actually affect the cosmology are all gone? And that's why things are unfair in the way they are -- because there's no one tinkering with them?)