What's so hard about it is that few individual things feel like "something you don't want others to have access to", yet in aggregate the individual things and the connections between them can become such.
On top of that you are putting the responsibility on people to "think of every bad use of this information which could happen, and if you are still happy, then post it". Which is an impossible task. Much better to enumerate what can happen, what it will be used for, which can be made a limited set of things, and then if you are happy with that, post it.
On top of that you are putting the responsibility on people to "think of every bad use of this information which could happen, and if you are still happy, then post it". Which is an impossible task. Much better to enumerate what can happen, what it will be used for, which can be made a limited set of things, and then if you are happy with that, post it.