Yes you are right. This is Marx 101 and has been understood for 170 years. It's called the increasing organic composition of capital and drives the declining rate of profit that in turn drives imperialism, the declassing of the western industrial proletariat, and the march to world war.
There's some kind of missing link here between p2p and "I write for a living" that I don't think is going to be bridged any time soon. Funding and p2p / independent might not be compatible organisms in today's social and economic environment. We've had the tools for this for decades and it's never been achieved at scale and sustainably. I don't think it ever will.
True. I don’t think it was ever successful, because it requires a strong ideological point of view from the people who are supposed to support this idea. With so much distraction in the digital world today, this seems close to impossible.