I personally do not care about privacy. I see no reason why I should.
It's just my opinion. I know other people do but please don't generalize.
Now you can decide whether you want the courts to have any ability to connect that crime to the medium that you were communicated via, or whether that information should simply vanish in the ether, leaving anyone to blackmail or extort anyone else from the safety of their own home and behind an anonymous Internet connection.
you've, in fact, made the opposite point to the one that you meant to :) when crimes start getting committed, sometimes society needs recourse.
But we were talking about privacy, not anonymity.
My argument is that even if you don't have secrets, someone with power over you (politician, judge, general, CEO) may, and you should want their secrets kept.