The most common argument used in defense of mass surveillance is ‘If you have nothing to hide, you have nothing to fear’. Try saying that to women in the US states where abortion has suddenly become illegal. Say it to investigative journalists in authoritarian countries. Saying ‘I have nothing to hide’ means you stop caring about anyone fighting for their freedom. And one day, you might be one of them.
They may know everything about you right now. But they don’t know about your future self, how you can change, how you may be an entirely different person in as little as a year. Data is useful, but it is more useful the more updated and recent it is.