I'm not really sure what "owning your data" means here, in practice. If you're sharing it with other people / pods the best you can meaningfully say is that you

I'm not really sure what "owning your data" means here, in practice. If you're sharing it with other people / pods the best you can meaningfully say is that you own a copy of your data, as does anybody you share it with. In terms of privacy, I don't really see how this is better than Facebook. I don't have an answer to your question. Broadcasting information while also wanting to keep it private is, as you say, a tricky problem.