15 years ago, when I last did a job involving image manipulation;
[Mostly painstakingly touching up by hand scratches and dust marks on archive photos ]
the employer stipulated that legal licenses must be obtained for all software in case of unexpected audit.
PaintShop Pro was fine enough for the job, and much cheaper than Adobe.
Also free copies of older versions were available with PC magazine CDs.

Though last thing I remember is around 2003 paintshop pro was buggered by newer versions...???