Not to mention the really simple fact that DNA evidence only identifies you as being at the scene of a crime, not having committed a crime.
And that one in 3 million DNA samples match when compared. Put everyone on the database and you instantly have 19 innocents who will be hassled by the police when a crime is commited where DNA is left behind.

I'm fundamentally disappointed that the law lords didn't throw it out first (just shows yet more need for a written constitution to protect us), but at least the ECHR did something useful
Hassled is not the same as being spoken to although they are obviously on a sliding scale.