There might be confusion about global moderation. This is what we do:
We delete images/videos of:
- CSAM (called cp colloquially, nudity of minors/under 18 year olds)
- bestiality (sex with animals)
- necrophilia (sex with corpses)
- "animal crush" (torturing animals)
- probably some other stuff
We delete textual content:
- incitements (example: "let's kill all the klingons")
- threats of violence (example: "tomorrow I'll shoot up the school")
However there's some leeway with this, since most written things aren't serious, written with comedic intention as sarcasm or irony or parody. We delete since retards like Brenton Tarrant and the rest made it questionable if these are just bad jokes or not.
We also delete spam and flood. These are advertisements, repeated messages etc.
We also get many user requests to delete this or that, some looks reasonable, some aren't. My main suggestion is always ignore.

If users complain about moderation on a board we also suggest to open your board and post your stuff there.
The necroposter could post these dead people reports on his own board if he wanted to. The schizoposter on bb can open his board where he can write his stuff about whatever he wants. If people want to read it or interact with it, ask him questions they could do it there. If they want.