> but it seems like those who get the most benefit from free labor are large corporations.
One factor is the lack of adoption of copyleft licenses. The proliferation of permissive licenses turned into a backdoor for corporations to privatize volunteer work. We should adopt copyleft whenever possible. Stallman is right on this.
> The Linux kernel's license is copyleft, which has done all of zip, zilch, nada, zero, to prevent large corporations from benefitting
You have it backwards. The goal of copyleft is not to "prevent others from benefiting". The goal is to potentially benefit from the adoption. If someone uses your copyleft library and fixes bugs in it, you can see their fixes and bring them back upstream. So you benefit from their work.
There's absolutely nothing wrong with a company using liberally licensed OSS to make money. It's not a zero sum game. The contribution from these companies could be considered to be the benefit to the end user for creating the final product (that includes the OSS), and at a lower price than it would've been had they had to make the equivalent OSS privately themselves.
There cannot be an OSS license where the user of the OSS who don't make money don't need to pay, but a corp that do make money pays.
My experience is that people tend to think "permissive = good, copyleft = baaad" as a first approximation. And then "copyleft = GPLv3".
But there are copyleft licenses that are not viral at all and just force the users to distribute their changes to your library, e.g. MPLv2 and EUPL.
I don't understand why one would use a permissive license versus MPLv2 or EUPL.
MPLv2 and EUPL are actually underrated and freedom-promoting for both developer and users. The true successors to the GPLv2 with loopholes closed.
GPL3 gave copyleft a bad name and everyone decided to give away their labour for free.
MPL/EUPL are the spirit of "you can use it, if you spend half a million writing a completely separate module of course you can keep it for yourself, but if you change the actual source files that everybody uses you have to share, so everyone benefits."
Using Linux as example it means one could write their own proprietary driver for their proprietary device, but optimize, say, the memory allocator, please share it so we all benefit.
The Linux kernel's license is copyleft, which has done all of zip, zilch, nada, zero, to prevent large corporations from benefitting from the enormous amount of free labor put into open source.
Git is GPL, this didn't prevent GitHub from becoming a multibillion dollar behemoth of a Microsoft subsidiary.
The value which companies capture is in using software, not modifying it and selling a proprietary version of the modified code. The only way to sustain this misapprehension is to notice every time permissively licensed software makes a company some money, and studiously ignore it every time copylefted software does the same thing.