...but practically how do you do it?
The parent comment is quite right, going from 'pay x' to 'pay y' is one thing... but from 'pay nothing' to 'pay anything' is a massive and difficult step.
You can't make it mandatory; theres a glut of stuff out there, and people will just move on to the next free (perhaps crappier, but free!) version.
'business innovations may help' is just a nice way of saying 'well darn, nothing we've tried in the last 10 years to fix this has worked... hm. Don't really have a solution for this, but it'd be great if someone figured one out!'
...which I totally agree with, sure, but its not really helpful or practical.
Seriously, nothing people have tried (tips, patreon, foundations) has worked very well.
No one is going to solve this problem any time soon.
Of you're an open source library author/maintainer, you've got to acknowledge you're not just magically get rewarded for your efforts; you have to work for it, and (probably, for most people) your attempts to monetize it will fail.
The same is true for all creatives.
If I had an answer to that, I'd be a full-time fiction writer. :)
Seriously, I suspect most people aren't going to ever make a lot from creative efforts, which we'll lump open source libraries into; the vast majority of us are going to be much farther out along the low long tail of the compensation curve.
I suspect the only thing that will help -- not to the degree that everyone will be able to make a living wage doing whatever they want, but to the degree that more people will feel like they're getting something back for the time they're putting in beyond the Warm Fuzzy Feeling of Sharing -- is a cultural shift of sorts. We need to uncouple the concept of "zero marginal cost" from the concept of "should be free." (I'm aware that leads down a whole rabbit hole about IP and "piracy," but I'm leaving it aside.) In the open source world, we may all say we're here for the free-as-in-freedom part rather than the free-as-in-beer part...but we're sure disinclined to pay for those beers.
Who gets to determine what is “fair compensation” and to whom?
So based on supply and demand, i.e. prices?
In a pure supply/demand market races to the bottom can and do happen.
There is an unlimited supply of people who say they would like to write novels, make programming languages, play soccer [professionally], or make video games. The supply of people who have the drive and patience to complete a novel or programming language or video game for free or on spec is arguably much smaller. The same is also true of open source libraries. There may be an effectively unlimited supply of GitHub repositories containing new JavaScript frameworks and template languages, but the majority of them haven't gotten very far past the README file. And, we haven't even addressed the question of whether they have the skill and talent to make a good novel or programming language or video game or open source library.
Having said all that, I think the original article is on point in at least one crucial respect: all of these cited kinds of work require a huge investment of time, and it's very hard to sustain that investment without money. This is why I always get very frustrated with the particular kind of pseudo-libertarian who blithely asserts that artists and writers don't need to be fairly compensated for their work, because clearly they'd keep doing it solely out of the love of creation. In reality, artists and writers--and open source programmers--aren't likely to put in "second job" level hours without compensation indefinitely. They're going to have a family, or develop more relaxing hobbies, or possibly just get frustrated by the ongoing effort.
I don't know if "business innovations" can solve this problem, but I think it's worth looking for more ways for developers (and writers and artists and...) to bring in some kind of stable recurring revenue.