Not only do I freely delete my own content whenever I feel like it, I often resist posting it in the first place. I just had my Yelp account removed including over 100 reviews because, well I was just over it and it was time to turn it off. I’m increasingly becoming more concerned about privacy, because there are just too many crackpots in the “heavy web user” demographic.
Not sure where this altruism about web content comes from. It’s your words and if anyone really cared, they’ll remember what you said. The ephemeral nature of the web is a big part of what makes it unique.