4chan is not only /b/ and porn, there are surprisingly good SFW boards too. Well, maybe "SFW" is pushing it a bit, since the tone is still 4-chaney, but then look around the technology, cooking, or traditionnal games boards: you'll be surprised.
Oh, I'm well aware of that. /b/ is (arguably) the worst part of 4chan. 4chan has much more than porn, but it also has a lot of porn.
The world wide web has much more than porn, but it also has a lot of porn.
This was also true of Usenet.
/sp/ is honestly one of the funniest places on the internet.