There are multiple discussions around censorship on AO3. They cross each other and Tumblr sometimes truncates a post’s text.
There is the “Report AO3″ to the FBI for allowing underage fic” (Fanlore write up here)
There are posts riffing ‘On setting up a Black fandom archive” to address racial bias/racism in fanfiction (see this thread)
The fans discussing racism or building new archives (for any reason) or AO3′s need better tools for filtering and searching are not necessarily the same fans who are (1) advocating reporting AO3 to the FBI for allowing underage fic, or demanding that (2) AO3 be shut down or (3) that underage, rape, incest fanfic should be banned from AO3.