Neither the statute of limitations nor uninforced laws against misuse are of any help in these situations. Data that are not purged may become part of your public identity, either now or for future generations. One reason for discussing and building secure systems is to see if they do provide an alternative. New technology often requires changes in practices. A change in human nature is not required, but rather a change in people's conception of their rights.
History provides many examples of such changes.
For documentation of a few examples, see our Constitution. In this case, we may not even need a new idea, but rather simply a recognition that a right that people thought they had is being threatened in a new way, and that there is an alternative to simply watching it vanish entirely. The government activities that pose the threat are not some sort of fixed environmental specs that technical solutions must comply with. The political process provides mechanisms for change, and technical demonstrations can be part of that political process. They may even change in a favorable direction for other reasons.