I would like this sort of functionality to mark an article as read without sending any commentary to the originating link. I’m not concerned with privacy. Quite frankly, I’m of the opinion that if I want something to remain private, I don’t put it online. Some control will fail or I’ll make an error in a setting and the content will be exposed or my controls will be breached.
In other words, I don’t trust the WordPress CMS to keep private posts, private.
What’s in my head stays in my head.