Sounds very much like they don’t actually secure the data itself, just identifiers. That is not really the same thing as ‘owning your own data’. Happy to be corrected by someone more technically literate.
“The top-most layer (layer-3) is the storage layer, which hosts the actual data values and is part of the data plane. All stored data values are signed by an owner key deﬁned in the control plane. By storing data values outside of the blockchain, Blockstack allows values of arbitrary size and allows for a variety of storage backends. Users do not need to trust the storage layer and can verify their integrity in the control plane. Our design beneﬁts from the performance and reliability of the backend cloud storage systems.”
SAFE is pretty radical, I don’t think you’ll find anything like SAFE despite hearing very similar sounding features touted in a lot of blockchain projects.
I’d need to read more about Gaia, but it also doesn’t sound like the aim is to release spare capacity to run the network. The incentives model is quite different at first glance.
It doesn’t sound like much of a viral formula to me tbh. It’s just more of the same, blockchains seeing the use-cases and desperately trying to fit the square pegs through the round hole.