Great discussion indeed: THANKS a lot for all your comments so far
As far as I am concerned, I only try to work with open source softwares: Gimp - RawTherapee, in particular.
In the long past, at work, I have worked with Photophop (version 8).
To be entirely correct, I still work on Windows 10, which, of course, is not open source (and yes, I do have tried Linux several times in the past…).
As regards Affinity photo its price tag is extremely alluring: no wonder many users are praising it!
On top of that, as soon as you buy it, it is yours for ever: no need no subscribe to anything any further (e.g. Adobe stuff).
The list of features it sports is surely quite impressive…
As already mentionend in this thread, compared to Gimp - Krita, for instance, Affinity Photo allows you to record macro. You can also do photo stacking with Affinity (see Hugin, Enfuse etc for these open source options).
It is indeed not surprising many users are buying this software right now…
I am not at all completely persuaded that Photoshop - Affinity strength - appeal is mostly related to their all-in-one package.
In my experience, when you are a professional photographer you usually work with Photoshop but for many specific tasks you might need to work with other commercial softwares as well.
I have always read Capture One is the best on Windows for tethering your camera. Lightroom has this feature as well but it is not entirely on par with Capture One.
The same applies to photo stacking. Photoshop has this features too but I have always read it is not usually judged on par with Zerene stacker or Helicon.
In my opinion, most “informed users” do not want to switch to open source software for many important reasons:
Lack of good professional documentation: video tutorials, books etc.
Important missing features for PROs: e.g. tethering with your camera, stacking features for macros, CMYK, LAB, macro recording etc.
Lack of professional - commercial support.
Most photographers work on Windows - Mac, whereas the open source softwares are usually developed on Linux.
Just think at Darktable which has been ported to Windows only last year.
Krita is missing some features on Mac.
The Gimp GUIs is supposed to really improve on Windows only with the next 3.0 version, through the GTK 3 toolkit (e.g. thanks to the better tablet support on Windows).
Features available BUT not on par with the commercial ones.
Lately, I have worked with the Free selection tool (lasso) with Gimp 2.10.6 and it was a real pain compared to my old experience with Photoshop…
Drivers are not on par with the sames on Windows - Mac (e.g. the Wacom for tablets are sometimes more buggy on Linux or difficult to set up properly).
Most important of all, in my opinion, most photographers do not want to risk their precious business “only” to save some money thanks to the open source softwares…
TIME IS MONEY: therefore, you do not want to start- learn from scratch your professional workflows : e.g. learn new different shortcuts; new places in the GUIs where you look for you preferred tool, etc etc.
In my view, it is only in these recent years that the overall quality of open source has really improved.
I am thinking of Gimp 2.10.x, for instance. The 2.8.x versions were good but they were strictly related to jpeg (8 bit stuff). The 2.6.x versions were weird with all their floating windows
Krita is extremely powerful right now but it was quite buggy in the past: e.g. for the text tool, the G’MIC support, the vectors options (through Karbon). Its new text tool is quite still annoying right now though…
Just my 2 cents and sorry for the looong rambling…