someone who knows everything about you can easily manipulate or even blackmail you
To that end, the ability for people to not only fabricate completely new evidence, but also manipulate existing evidence, I think deserves a lot more attention.
For example, imagine the damage someone can do simply by taking leaked corporate data and slightly messing with it. Who second-guesses the accuracy of leaked data?
the “nothing to hide” argument implies that if you want to keep certain aspects of your life private (i.e., hidden), you must have done something wrong
What has also become more sinister as of late is that the definition of "wrong" can change at the whim of whoever is running your government right now.