I suspect most people (including me) are probably lurkers/upvoters. The lurkers will have more to say when the new season is live :)
Also, where does that subscriber count come from? I looked at this community via 3 different Lemmy instances & saw different numbers on each of them.. maybe that number is just specific to the amount of local instance members subscribed to that community. Here at lemmy.zip we're at 18 subscribers for !futurama@lemmy.world