Everything is equivalent to proof-of-stake plus overhead. If you have the stake, you can show it in proof-of-stake, or you can buy mining hardware and burn electricity in POW, or you can buy storage and prove it via "plotting" (in Chia) in proof-of-capacity. Two of these require you to exchange stake for something else that you then dedicate to the system. Unless there's something in the protocol unique to non-proof-of-stake then it's comparatively wasteful.