I disagree - the right of users to assert control over their identity and data supersedes your desire to control or use that data for your own purposes, or your desire to have the web act as an immutable historical record, which it was never designed or intended to do.
I agree that Reddit threads with deleted content are annoying, but that's an implementation detail Reddit chooses to have and could likewise choose not to have (the way Hacker News chooses to make it impossible to delete user accounts, change usernames or delete comments after a certain time.) But the premise that people should be allowed to delete content from the web at all shouldn't be up for debate.
>I think one-sided deletion isn't the solution, fine-tuned privacy settings (and thus hiding and possible recovery) is.
Both can be solutions, but I believe the former is a necessity.