This is a topic that some of us have started to go into a bit in yesterday's daily discussion, but I think it's worth splitting out and continuing more. I think one cause of people being so sensitive about content that they think doesn't belong on Tildes is because the site currently feels like one overall shared space, instead of many individual groups that might have their own different types of acceptable content.
A lot of this is just because the site is so small right now, and will probably gradually change as it grows. Quite a bit probably also comes from the fact that new users are subscribed to all groups automatically, so to them, everything just feels like "part of the site", not really separate groups that they individually opted into.
What I'd like to discuss is if there are any ways we could help make that separation more clear—should we stop auto-subscriptions to everything soon? Could we try to display posts from different groups in a more distinguished way? Any other ideas for ways to make things feel a bit more "separated", even while the site is small and there will probably be common users across most groups?