My own courses must be counted as closed. Only students with the right permission and login have access. It gives me a security and a control. I will rate those who participate and I get a clear overview of what everyone is doing.
But when I see it from another point of view where I am a student, I am much more positive about open learning. However, ONL172 is the first online course I have attended that I experience as being interactive.
I have the same experience as you! All my courses have been "closed" and no material has been shared outside the course. After participating on ONL172 I have found out that sharing is not so scary, when you share something you have been working on together and in collaboration. I will try to encourage my students to share more in the future.
SvaraRadera