But certification in cyberspace could be much more narrowly tailored. The technology could make it possible to selectively certify facts about you, while withholding other facts about you. But there is no necessity that it will develop like this. In these architectures, there is no simple way to limit what gets revealed by a certificate. Under this architecture, more is better.
Nothing enables the individual to steer for less.
The difference between these designs is that one enables privacy in a way that the other does not. Thus whether the certification architecture that emerges protects privacy depends upon the choices of those who code. Their choices depend upon the incentives they face. The example about identification is just one among many. Consider another, involving information privacy.