But what about someone with mental health problems? Depression or anxiety? A past drug addiction, or merely alcoholism? A criminal record? How about something as "innocuous" as a drunken one night stand while in a committed relationship? Is it so difficult to imagine how, if widely known, these facts might impact someone's ability to hold down a job, or their relationship with their neighbors?

For other people who do have things they'd rather keep private, it's not just in their head-- it can have a wide variety of implications in your interactions with people & society if it becomes common knowledge. If nothing else people will look at you differently. And a lot of it has happened in the past and is unchangeable, and therefore unactionable in the present.