I'm often hearing that 4chan is "unmoderated" or has "the bare minimum of moderation", which just doesn't line up with reality. Many boards have strict and specific rules about what content is allowed, what is banned, and how said content should be presented. Just listing some rules off the top of my head: you must have a minimum number of pictures to start a thread of /s/. Normal hentai porn goes into /h/, weird fetish stuff goes into /d/. No western art allowed on either. Content that breaks the rules gets removed within hours, sometimes minutes.

If you see something that you find disagreeable on a 4chan board, it's likely there because it's allowed to be there. They aren't struggling with moderation. The fact that it's still online in the clearnet after so much media attention proves that they have enough jannies to take care of the illegal stuff at least.