>>280876595
Part of it is that /a/'s activity has fallen off a cliff since S3, to the point where barely anything outside of the Weekly Jump lineup can sustain discussion anymore. But also Osomatsu-san seems to have one of the most jaded and negative fanbases around. Lots of "genwunners" who are just fans of their own nostalgia for S1, not the series itself. You have people acting like S2 was the worst thing that ever happened to anime as a medium because Dayon and Dekapan got a couple more minutes of screentime than they would have liked. Now people are bitching about S4 having some slower, moodier episodes early on like the other three seasons didn't have those kinds of episodes too. A lot of this crowd dropped the series years ago.