Face to face communication has always been available freely and anonymously. I'm not quite certain that any other form of communication has ever been either freely available or remotely anonymous for anyone remotely like an average person.
What communications platform has it ever held true for?
1.) Telegraph -- cost money, not universally accessible, open, message assured to be read by at least 2 3rd parties.
2.) Mail -- costs money, need a registered address, handled by a quasi govt agency, can be read by 3rd party.
3.) Land line Telephone -- costs money, not universally accessible, requires registered address, every action is logged including recipient and duration. Calls can be listened to by 3rd party.
4.) Cell Phones -- costs money, not universally accessible, burner can be had with no address or name. Calls can be listened to by 3rd party. Location tracking available.
5.) Home Internet -- costs money, not universally accessible, requires registered address, everything routed through ISP who keeps user logs, network that can intercept.
It's unclear to me why the service layer attracts so much attention, when the underlying network layer currently makes it largely impossible to have what you want for the average person. Having anonymity at the service layer is almost confusing when the underlying framework guarantees it is largely not real. There are all sorts of options already available at the service layer that can give all sorts of false appearances, many fewer at the network layer to make those false appearances turn real. Twitter and Facebook and G+ are trivial issues in comparison to getting around the fact that backbone and access points are a network owned by 3rd party intermediaries (just as with all the previous communications platforms above).