Michael Tsai posted two links with different authors opinions on the subject. The HN conversation that ensues from the original link, by Seth Godin, is highly interesting for the myriad of points of view. Let me share mine.
I grew learning Turbo C and Turbo Pascal (after some Z80 assembly). Later I developed an enthusiasm for Delphi, a truly complete environment for Enterprise Windows GUI development, which included the excellent VCL and some data-binding. Back then, there were (and probably there still are) companies that provided complex VCL components, much as those that now provide ActiveX, WinForms and WPF components. Open source wasn’t still in the map, so if you needed any library your options were limited to those made available by the development tools vendor or commercial third parties. There were of course free (as in beer) libraries, but nowhere near GitHub level of availability.
If you were a company or a professional developer working on your own, you would pay handsomely for your tools and any additional library that would let you complete your project sooner and easier. Nowadays tools are mostly free for individuals, but they can get expensive for companies. We have a huge repertoire of programming languages, libraries, and tooling available for free, and yet there are companies that thrive providing better tools, better integrations, better support than the community. You can go cheap and grab you some Visual Studio Code or you can get a commercial IDE for a much better experience. Anyway, great software is being produced with cheap or free tools, and with paid tools.
And the same goes for all sorts of software. Blender is such a great 3D application available for free, but it cannot compete with Maya when you need that kind of software. People or companies that use Maya are using it because it makes their life easier, which in turn means they can save money or be more productive. There is a place for cheap software and there is a place for complex, well supported and expensive software.
Personally, I buy software when the free choices are worse. I also like to buy the software I depend on to support the developer, because I know that without that support, that software may eventually disappear. As of now, I bought and use MarsEdit, Scrivener, Textual, NetNewsWire, OmniPlan, Affinity Designer, PCalc, Pixelmator, Folx, Paw, and some other I don’t use much. Each one of those is used regularly. They all provide great value. I don’t even know what the free alternatives are, I don’t care anymore.