Note: This post was extracted from a private conversation, so the tone and structure might seem a bit different (as well as missing citations). I decided not to mess with it too much to avoid damaging the essence of it.
Something a lot of people forget (or never knew) is that free software was created to escape the control of commercial software, specifically by programmers who wanted to escape that world themselves. We've had free software long enough that a lot of people don't remember what that other world was like, so they fall right back into the trap free software was created to escape.
It's also worth noting that this "old world" is pretty distinct from the timeline of the personal computer. These were mostly programmers working on minicomputers and mainframes at universities and corporations. Personal/microcomputer software was mostly free and open for the first decade of the personal computer revolution.
Along both fronts capitalists convinced people they were incapable of building their own computers and writing their own software, either by controlling the means of production or by driving-up complexity so only experts could do the work.
This would sound crazy if not for the fact that it's been done before. Consider the relationship between books and the church before the arrival of the printing press. The main difference being that computer industry capitalists managed to succeed where the church failed and put the press/computer back on the high shelf
Anyway, I say all this because the free software we have today, how it came about, didn't really take any form of sustainability into consideration. It was good enough that it could exist on the "waste heat" of professional programmers working in their spare time (or stealing a little from the boss). I doubt anyone there at the beginning could have imagined that most of the worlds commercial software would eventually run on top of free software while doing relatively nothing to support the free software work.
So to fix this I think we have to go back to the beginning (maybe even before) and redesign how free software gets made and look at its goals as something broader than simply escaping proprietary commercial systems. When I think about it this way, I don't see how you get there with the context of capitalism. Ultimately it's not a problem of supporting free software but of supporting free workers, and the solutions for that require broader changes.
Without that, I think we're relegated to making deals with devils or eking out an existence in the cracks of the pavement.
This might sound doom-and-gloomy but for me it's encouraging, because it explains why everything I've come up with or tried so far has failed to find a solution for this!
Knowing that there's no free software without free people points me in a more productive direction, and to a problem whose solution produces a much, much bigger lever.
