It can screen visible stigmas, so that messages cannot use that information as a part of their content. It can operate as a factor in creating new normative patterns of interdependence in relationships. It can enable a different kind of stalking. But stalking still requires a person to be the stalker and to have the mindset that will lead to stalking. Second, this is a free speech issue.
Censorship has awful potential.
It becomes an issue whenever there is a quasi-public medium to which many have access and in which some object to the preferences others display for the nature of the messages, both verbal and visual. Pornography is available on the Net. Pornography is available. Once television took that into account. Now, we are treated to commercials on hemmrhoids.