Reddit still allows far more leeway than either of the others, but that's why I said "until recently" anyway. Reddit's PR problem was mostly formed prior to that though. Reddit became a place a lot of people only heard about when a story about child porn, upskirt pics, leaked celebrity nude photos, revenge porn, and other socially unacceptable material would make the wider press. The fact that they've made some tiny strides away from that now doesn't immediately fix the PR issue.