The Dollars is a fictional group with in a fiction that becomes real because a few characters, including the main one, create a forum and talk the group up. This forum is a recreation of that and the premise atone point was the same.
2-ch is still active and a big deal in Japan. Honestly the whole Dollars concept is borrowed from the what image boards are used in Japan and was sort of a re-imagining of how otaku might group and use their collective to change their image.
Oatku are viwed negatively in Japan, granted japanese otaku take things to a whole other level but it's not unlike how the media label wackos "metal heads" or "gamers" in the US.