Yeah, I get what you mean. Native applications store your data locally, which is privacy-friendly, but sharing is hard. SaaS brought easy sharing of data, but it also brought data mining. So the goal is to have data in the cloud, but isolated, rather than in a big shared database in some SaaS provider.

If you trust the privacy of cloud providers, you can spin up a server and use https://sandstorm.io/, which is designed around that: private infra, with granular sharing of data.

If you don't, you need local compute and encryption. Keybase would be a decent example - while you can't use your own cloud account, they only see encrypted data.

That said, there's a reason a lot of people deleted their Keybase accounts when they got acquired by Zoom. Data mining is very enticing, so outside of projects ran by idealist volunteers - which will always have a hard time competing with funded companies -, how do you keep developers from adding mining abilities even to the native/self-hosted applications?

What about https://blockstack.org/? With this approach you own the data

Wasm and weed is a powerful drug.