I suffer from Generalized Anxiety Disorder, I'm currently trying to get the right medication for it. But one thing I suggest for people with social anxiety, is to go online more whether it's 4chan which is anonymous, other image boards, forums, online games, or anything else online that helps you talk to people. Kind of like the OP said. But these people have to realize nothing good will come of it unless they make that first move, which it will be difficult at first but it's definitely possible, just keep trying to start a conversation online with people you don't really know, people who have no clue who you look like, how you act in person, who you are, etc. Talking online reduces a lot of anxiety, because there's nothing really to judge at first. How I became a little more extroverted was that I started making for friends in games Minecraft and WoW specifically and it helped me be a bit more extroverted and more open. Now it's not going to completely remove your anxiety completely, there will still be times where you're just too scared to strike a conversation, and I still go through that. But doing this does help a lot more than a person would think.