Because probably dang and company tries to nip the bud when the link is posted. Since that most that pass that filter are relatively uncontroversial (they're th

Because probably dang and company tries to nip the bud when the link is posted. Since that most that pass that filter are relatively uncontroversial (they're things that interests some and silently ignored by others), they only need to actively monitor those with inherently high-level controversy (like partisan politics).