The inherent flaw is thinking that “privacy” is something that the courts are capable of providing. They aren’t. The most that government/courts could possibly do is make it illegal to generally and indiscriminately retain IP address records. But that only protects you from law-abiding privacy invaders; it does nothing to protect you from criminals who would use that information nefariously.

When you take adequate and appropriate steps to secure your privacy, it doesn’t actually matter what the courts have to say about “privacy”.