...Is a total sham. Everyone in /nihongo/ that professes to be Japanese is actually just an annoying non-Japanese posing as a Japanese.
Most people I know that are total otaku (since this word is Japanese in origin, I'm assuming that the plural and the singular are the same) have not heard a thing about 4-ch. And when I first came here, the running joke was that there are only 3 real people that post on 4-ch. So, with this incredible obscurity among English speaking otaku, what's the chance that Japanese otaku know about this place? Simple. They don't.
Discuss.