I think it's two parts. One, the team sucks, so people don't follow the team as closely, so many of the more casual fans just aren't watching the games and posting anymore.
But also, the toxicity around here has driven away many of the more reasonable posters. All we have left is a hive mind echo chamber and a few stragglers butting up against it. The Sens reddit community is very very different than hfsens.
edit: To be clear, I think this place is less toxic than it was last season, since the admins stepped in and the mods started moderating more.