My private data isn't worth much since it's highly context-specific to me, and only I place value on it since I know how it all works and how it can be leveraged. A random person exploring my private data would be eternally lost as to what to do with it. That doesn't mean I share it publicly just because it has no value to others.
There are people who hoard[0] data all to themselves on storage which is getting cheaper as each year passes.