Is that really a mystery?
First, you'll never have the same burst that you have when something starts fresh. Second, like any other business, even free content creation is subject to the phenomenon that existing product discourages new entrants, because people think-- it's already being done, I'll never catch up to their audience, etc. Then there has to be a lag before the gap becomes apparent, people notice the market opening, and new projects start up.
Then, a lot of the projects under discussion closed up within the last year, and new ones would have arisen this year, but, you know.
It's rather obvious and I don't think it should have needed to be written out.
Damn! Sorry Mr. Grumpy Pants. Someone woke up on the wrong side of the bed.