We rely on self- and community-moderation. As long as content is flagged appropriately, we allow and embrace content that's often banned on other platforms, such as artistic nudes.
Not everything is allowed, though - here's the list: https://www.flickrhelp.com/hc/en-us/articles/20529310987796-...
We do have real, human, in-house customer support. It's good and fast.