The devil is in the details.
You are anonymous online (no one knows who is on the computer that is connection), however your computer is known/recognised. (Choose who you affiliate with carefully, Mac or PC?)
What people don't consider is that most of the internet now is proxied/cloudbased. That means the days of connecting between two random machines being missed is near gone, since the way a cloud system works is to maintain integrity through mirroring.
Those mirrors are actually copies of the internet as a whole that a number of governments have agreed upon keeping maintained for longer than just an instance for the future prosperity of the internet should for some reason the internet suffers a cataclysmic failure, a couple of men located around the world can "reboot" the mirrors back into effect to try and repair some of the data loss.
There is the added factor that those mirrors are used to hunt pieces of information down from the point something is of interest, which means over time through analysis using some of those vast super computers you hear about (and probably just assume only deal with particle acceleration data) will eventually allow a composite of a particular "nodes" activities. (I use the turn node to reference that your computer information makes up part of that node data)
All in all, anonymity is only a concern for:
- those that are persecuted in countries that have appalling human rights records and concern themselves with their need for freedom of speech or otherwise.
- For those that are criminal to hide their crimes
- For those that are suffering from criminals targeting them.
- If you happen to be apart of the "Great Game" (Spycraft).
Alternative to attempting to hide is be transparent, as funnily enough the more someone has to say, the less people want to hear

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