Software Piracy: the perspective of an indie developer.
I've been developing plugins full-time since 2015 and they have been pirated more than once. Depending on when a plugin was pirated, it could kill sales altogether or just have a minor effect. Timing is everything.
Usually, when the marketing campaign is running full-blown for a new plugin, it's when most of the sales are done. If only 1 person purchases it and redistributes it on a piracy website, it'll usually mean that 90% of my sales are gone.
If it's an old plugin that is illegally redistributed, then it usually doesn't make as much difference. Not enough for me to have a clear idea if it's actually hurting my sales.
Virtual instrument development is long and tedious, it requires time and resources and it often implies buying other software and hardware in order to run tests on different machines. The value is not only in the time it takes to develop the instruments, it's also in the gear it requires to create them.
And then there's the maintenance aspect of selling software; they all need to be updated at some point due to technological evolution and OS upgrades. It adds to the cost of development.
In the early beginning, my plugins were pirated a lot. So I decided to stop selling multi-formats packages that offered everything for a single price and split everything up into different versions you can buy separately. It made a big difference!
Another aspect of piracy that is often overlooked is its impact on free software. I offer more than 20 free plugins on my website and it's being made possible thanks to people who donate and purchase my commercial instruments. Without them, there wouldn't be as many free plugins available to the general public, including schools, universities, and community centers in poor countries.
From a practical point of view, I don't really care about software piracy, but when it becomes big enough to hurt my business, I don't have much choice but to limit its reach. Otherwise, I might as well close up shop and sell common goods in a convenience store. But then, it wouldn't be as fun as creating cool virtual instruments for musicians. :)