

Well, hobbyist projects are surely not the only pillar of the open source systems
Your hunch is correct, they are, because the differentiator between open source and walled garden projects is freedom, and freedom will spontaneously generate projects based on an unfulfilled need. A paid market by itself will not.
In my early days of programming (late 80s), I was copying code from books and magazines. Then came windows and mac, and these were far less friendly to devs, and became more and more so.
Most of these tools were born of need and want, not because any infrastructure existed to pay them. Look at the list of apps in frdroid; most are very obviously solving a problem unique to the dev.
And there is one more thing to account for: for all the apps and scripts you see in a public code repo, there are many times more than that living on someone’s HDD that will never see the public eye.
The point you’ve ignored in your article is that this is simply the split free market creates. We’ve had this issue since the invention of transmissible ideas.

No, the logistic problem Google “solved” in making YouTube functional and free was born from a time when dumptrucks of VC money made it viable. It will never happen again, regardless of innovation.
This is not a technical problem, and in the case of the YT monopoly, it’s beyond even a people problem. Google got the money, and google won. It will be very difficult to unseat them.