This site grew when the old official site was a troll-fest that closed down soon after. At the time, it was either this place, or a still fairly new HFBoards to discuss the Sens in a message board setting. Since then, the Sens have re-opened their message board, HFBoards is easily the biggest hockey discussion site on the internet bar none, and a large part of the active membership was young adults. 10 years later, those people are 30+, many likely with other priorities in life (not everyone posts on the internet for life). And as BD alluded to, there's also a change in the discussion model on the internet with many message boards having declining activity simply due to Twitter and such.