Why privacy because a citizen has it and a slave does not. The freedom to keep yourself to yourself versus being slavishly continuously exposed to the inspection and judgement of others. Privacy is about the choice to be private, loss of privacy is the loss of that choice, that choice being denied and even worse the association with public humiliation and degradation that comes with that loss of choice.
Now, strangely enough challenge those with power enough and you have to abandon privacy otherwise they will forcefully invade it with the claims that your attempt to maintain privacy is an attempt to hide conspiracy and seek to expose you supposed conspiratorial secrets with a life threatening armed assault. So requiring you to abandon privacy to a degree to enable them to spy. This as a personal defence, as they then no longer have an excuse for a physical raid, something they will be looking for in order to punish you via corrupt prosecution as punishment, not conviction, just the abuse of the prosecutorial procedure.