I only have anecdotal evidence but my observation has been that the set of things people decide to share is motivated by the facade they want to create. Once all that stuff gets analyzed in the aggregate, future historians will be able to paint a more complete picture of people's lives. My prediction depends on how ugly that picture turns out to be.
Ugly is culturally relative. Fifty years ago, people would be horrified to find out how many people were gay. Today, we're horrified to find out that gay people felt the need to stay in the closet.
Agreed, 'ugly' is culturally relative. I'm interested in what happens when cultural norms change a lot in the span of 20 years yet everyone's real history is public domain.
