Chia is not Proof of Work, FWIW. Their technical and business whitepapers are helpful resources for learning more about what they call "Proof of Space and Time".
Is Proof of Stake proof of waste? It has some of its own unique challenges, but I think it seems better in that it doesn't require committing lots of physical resources.
Officially, no, but it is an emergent property of their other responsibilities.
For instance, a government cannot maintain law and order without power, and a society without law and order is the definition of a failed state ([edit] well, more specifically one in which the government has lost its monopoly on violence). It's not an unreasonable interpretation to therefore say any non-failed state must retain power.
Just the amount of buzz and interest I'm hearing. One data point (which is the only one I can share without revealing personal info on this public site) is that my local hardware store sold out of 8TB+ HDD drives and, according to the employee there, that hasn't happened in many years.