So if someone attacked you or one of your loved ones, you would say "Set the attacker free because we don't want to increase recidivism"? Perhaps the current prison system is doing more harm than good, but the rule of law requires that laws actually be enforced in some way. There must be consequences for actions that are harmful to society. This is the goal of the justice system, and being able to execute warrants is a key part of that.

Likewise if you wound up in a highly unlikely ticking time bomb scenario, ie being kidnapped, you would probably hope that the authorities were using every means at their disposal to find you, up to and including going through someone's iphone. The likelihood of a dangerous situation doesn't matter to someone who is at risk, and for that reason society should be able to offer every aid to people who wind up in rare circumstances.

If you're advocating that we throw out our entire legal system and start from scratch, I'd like to hear more about your proposal. The system that we have now is the careful combination of interconnected parts, one of which is the power of a judicial warrant. We have to be careful about what we do in the name of privacy. Weakening one part of the system can threaten the whole.