If you have visited your AncestryDNA settings page today, you may have noticed a new section entitled "Privacy". Below is a screen shot from my page.
At first glance it looks like standard options you would expect to see on your DNA page. However, these settings need to be examined further. The Ancestry team posted a blog post today regarding the new changes to DNA settings. One important change sticks out (emphasis mine): "Customers can now decide if they want to have access to the list of people they may be related to and be shown as a potential family member for other customers with whom they share DNA." This statement refers to the first setting in my picture "You have chosen to see and be seen by DNA matches" (which thankfully is the default for existing users). I can understand if a tester doesn't want to see their own list of matches. Perhaps they tested and a family member is managing their kit or maybe they're not interested in genealogy. Or maybe they're brand new and are just starting a tree and just aren't ready to jump in and start reviewing matches.
However, to hide yourself from others' matches list may be doing a disservice to your DNA cousins. I know this may seem like a sweeping statement but let me explain. I am involved in a number of genealogy groups and have personally worked on a few cases where I was helping an adoptee or someone with an unknown parent locate their biological family. They typically just wanted to know their roots or want to reach out for medical reasons due to the inheritance of many diseases and conditions. By opting out, you're potentially denying someone that you're related to an opportunity to know their roots.
I'll give a recent example. I was approached by a young woman who was helping an older gentleman find his biological roots. He was adopted in Canada and wants to know who his biological family is. He has no intention of disrupting any lives, he just wants to know about the people he came from. Had I opted out as well as several other cousins he's been in touch with, he would not have any leads to pursue to find his family. I was able to provide some details on my family to help narrow down a family line that could be pursued further.
It may seem like a small act but I urge everyone to keep "opted in" to see your matches and be seen by matches. I view it similar to the public vs. private tree argument. I would rather you see everything I have and approach me with questions or even challenge me when I'm wrong (I've been wrong before and I will do my best to quickly fix my mistakes and learn from your documentation). I welcome all of my DNA cousins - I may not know how we're related but you are still family to me. You have a right to know about your roots and I will do what I can to help you.