It's interesting how people go to a certain board specifically infamous for posting that kind of stuff then are shocked to see said stuff, then generalizing the entire site off that one interaction. It's as if I equate /r/AskHistorians, a heavily-modded academic sub, to /r/(insert raunchy sub here).
The users from one are going to be around on the other. This is true everywhere. When Reddit banned various hate speech subreddits you stopped seeing those guys "just asking questions" about the inherent inferiority of certain races in unrelated subreddits anywhere near as often.
Holy shit, in what world is /b/ not full of gore and porn today. Outsiders can't help but make confident sweeping statements about a site they don't even use. This comment tree is laden with cringe-inducing posts, you think using 4chan is so cool that you're willing to pretend that you know anything about it?