What I do like it the streams is that they focus posts towards those who will appreciate them. Do you want to wade through 25 pages of things you don't appreciate or understand to find a meme you like? Why would others want to do that to find your meme? Fun is so lumped together with everything that good memes get lost.
That said, I think you are right about the number of streams. They are becoming so exclusive that their followers aren't more than a few people, and some are becoming competitive, especially, Boobs, Booty and Milfs.
Growing pains of the site, perhaps. I don't try to visit all of the streams.
I've also noticed less commenting over the past few days or so. I know many have become disenheartened by the departure of capt6550, and others. Maybe it's just something local to me. Maybe people are enjoying the weather.