Piracy is good in the same sense that evil is good.
The argument of the article sounds plausible and logical. Piracy is good as long as it happens to other people's software.
"Evil" also helps propagate the value of "good" in some sense. Otherwise people wouldn't realize that "good" is "valuable".
If everyone in the world only used pirated software, sure the software would be "popular", but would there be any more incentive for better software after that? Maybe not.
People pay money for things that they believe will provide them more benefits than their price. e.g. your employer thinks you will generate more revenue out of your work that what you are paid. You know why you are with your employer, so I won't tell you what you think.
This works in a similar way for say, a $20000 car which you will buy if you think it worth, otherwise you won't.
Economy works on people's illusion that what they exploit from other people is worth more than what other people exploit from them. Advertising adds to the illusion of worth of an object. (Image is Everything (unfortunately))