It seems everyone is missing the point of free software entirely and also don’t understand value and economics.
The point of free software is to make software that respects users freedoms. It does not exclude anyone including corporations. If you don’t want your stuff being used this way don’t use a free software license or dual license it.
Even if you sold it in the first place you are not entitled to the value that that person or entity made with it unless you signed a contract saying so. All this talk about market value and fair compensation is nonsense. If they got paid for the work do they then owe the people who wrote the tools they used to create the software? How about the people who created the text editor they use or the people who created the programming language they used? You can keep going and find all the places were they used things other people made that they never even think twice about compensating.
If you can’t afford to maintain a project because of a lack of funding then just stop doing it. simple as that. You don’t owe anyone anything.
This is not a problem with FOSS. It’s an economic system issue. I don’t see how paying FOSS developers more solves this particular problem. What people need to do is stop using proprietary software and relying on mega corporations like Amazon out of convenience, or at least perceived convenience.