The government in power today is not guaranteed to exist indefinitely. Power structures change, and there is no definitive way to prevent your government changing underneath you as you are a single voter amongst a sea of people with different priorities.
The only power you as an individual truly have is to lower your risk profile if such an adverse event were to happen. History has shown time and time again that governments can change dramatically for the worse in short timespans, and if they have data to use against you then they will definitely use it
Sure, but can you at least concede that this technical possibility eliminates the argument that these services can't affect those that don't opt into them? That's the argument I'm trying to make, not necessarily that a particular serial killer had his privacy violated.
The only power you as an individual truly have is to lower your risk profile if such an adverse event were to happen. History has shown time and time again that governments can change dramatically for the worse in short timespans, and if they have data to use against you then they will definitely use it