Compare that to the claims of the Indian government with the Aadhaar database. They have have made similar claims for that database, yet on several occasions, it's been proven that they have had massive data breaches, both in the access portal and in the basic encoding system of the Aadhaar ID card itself.
I don't know if I believe Estonia when they say they've had no data breaches or problems whatsoever, or if that's just bluff and bluster. Maybe that's something I could look into a little more in-depth.