So you're telling me that Serif doesn't know who bought their software on Apple? One more reason to be glad I moved away from the Apple dictatorship.
As for development cost, that shouldn't factor in, and for most other companies it doesn't. I was able to move most of my licenses from MacOS to Windows without any issues, including those from Adobe, Phase One (Capture One) and Anthropy (PortraitPro).
In this case, Serif is basically saying "we don't care that you were one of our early supporters who enabled us to be successful enough to enter the much larger Windows market. Too bad for you, now pay up again." I think I'll pass.
