OK. I fixed it. The problem was that I was using the Buddypress Nouveau Template Pack rather than Buddypress Legacy. The Legacy version has activities as the Group home page, while Nouveau has that weird thing where you have to click on the Activity tab to see posts.
I’ve yet to find out what other changes this has brought about.
It’s the same deal when I log in as a subscriber. When I visit a group the default view is “home,” which shows the group description. There are also links to “activity” and “members.”
“Manage the Groups default front page” only brings up three settings, and none of those seems to relate to making the “activity” tab the default. One of them — “Display the group description in the body of the group’s front page” — adds the group description to the activities page as well as the group Home page. What I want is for people who are visiting a Group to be able to see what has been posted.
What I’m seeing, whether as an admin or a subscriber, doesn’t fit with the description “Each group has a homepage. The group’s Activity Stream is the default Home tab for any group.” I’m wondering what I’m missing.