BuddyPress.org

So, I decided to give up on trying to figure out the code for that theme, and just went ahead and switched to Twenty Fourteen, and I have the same problem; no comments in the activity stream.

I realized, when I said the problem was resolved by switching to another theme, I was actually logged in, and that is why I could see the comments.

So, I still have the same problem, on two different blogs, there are no comments shown to logged out users, in the activity stream.