"In other words, when participating in networked publics, many participants embrace a widespread public-by-default, private-through-effort mentality... By focusing on what to keep private rather than what to publicize, teens often inadvertently play into another common rhetorical crutch—the notion that privacy is necessary only for those who have something to hide. Indeed, many teens consciously seek out privacy when they’re trying to restrict access to a narrower audience either out of respect or out of fear."
I disagree with Boyd's assertion of public-by-default, private-through-effort and that teenagers have to make a conscious choice on what to make private online rather than public, supporting the belief that privacy isn't needed if you have nothing to hide. When you post something to social media, you are making a conscious choice to post said thing. I believe the opposite: the default is actually private, and it takes effort to make that post public. As a result, I would say most teenagers take quite a bit of time to think about what photos they are going to show to their follows prior to posting. No one is going to post a picture of themselves without assessing how they look in it first. Many of the forms of social media communication Boyd includes in the chapter are pretty much extremely obsolete and outdated to a certain extent: blogging, posting on friends' Facebook walls, status updates, basically the use of Facebook as a whole.
Private social media is not an indication of someone having something to hide. Private social media is also usually not created out of respect or fear. Many people do not want strangers looking at photos of them and their friends, hence making an Instagram account public. In addition, I rarely post on my Snapchat story, not because I'm committing crimes, but because I understand that the majority of my followers do not care about what is happening in my life. If I wanted to share something, I would share it with my friends on my private story.
I think that Boyd's assessment of social media in teens isn't totally applicable to the current young adult generation as it is out-of-date. Despite the book only being published 5 years ago, social media use changes so rapidly that many apps and websites once widely-used fall out of popularity extremely quickly. I can think of several apps that were popular 5 years ago in middle school (Kik, Vine, Omegle, Tumblr, etc.) that no one uses anymore because they have been shut down or aren't trendy or fun any longer. It's not only the types of social media platforms that are constantly changing, but the way social media is used. Perhaps 5 or 10 years ago, it was common to post song lyrics to your hundreds of Facebooks friends, but that is simply not the case anymore. Teens today generally find people to share too much on social media as weird or annoying.
Lastly, I think it will be close to impossible for an adult to understand teen social media use and culture unless he or she is fully immersed in the experience (which the majority are not). There are so many facets to how we use social media that you can't get the whole picture just through research or interviewing someone. It could honestly be equated to a foreign country's culture or language: no matter how much studying you do, you can't completely understand it unless you're a part of it.