That's your defense? You asked for actual risks and when shown real, plausible ones recede into XKCD quotes. Clearly just a spoiler.
The point is that while you can use DNA to identify people in most cases, sufficiently motivated adversaries have more effective, cheaper, lower-technology approaches that they will use first.
Me shouting my sensitive private details in a crowded bar is entirely different from putting them on my webpage. There's even a difference between writing them down on a napkin or shouting them out.
I guess it's representative of the demographics here. Nobody capable of conducting themselves honestly.