>/b/
Seriously? At this point, even 4chan itself ignores that board, because nothing meaningful has happened there since... Boxxy? The main userbase is like 10-16-years old (and has been for ages), so while the number of posts the board gets is astronomical, it amounts to nothing.
4chan is, in a sense, a relic from last decade, with /b/ being a relic inside a relic - a relic from MID-last decade.