I sent a message to a 4-6 cousin match with a locked tree in early Sept (my tree is also private). I got a reply from her a few days ago. Because you haven't had a response yet, doesn't mean you won't.

But in answer to your question, I guess not everyone takes the test for the same reasons, and for some people, connecting with other's doesn't seem to be a high priority. I'm trying not be become frustrated and respect the fact that it is their choice...