Also important: it is the kind of software that HN readers are likely to buy. Knowing about the crappy post-purchase experience is valuable information to anybody considering the purchase.
It also shows why Apple gets things right by concentrating on customer experience. Buying VMware from the Apple App Store would have been an entirely different experience.
It's also an area where businesses have to work constantly to resist legitimate forces: the desire to know more about customers, the desire to reduce piracy, and the desire to outsource tricky business processes. VMWare might be an extreme example, but most checkout processes trend in this direction without conscious effort.
There are an infinite number of ways to communicate how not to do things. Enumerating them only serves to decrease the entropy rate.
What I suspect is most people enjoyed this article because VMware made a fool of themselves, but not, as you suggest, because it provides an enlightening anecdote that will inspire the reader to avoid a common pitfall and yield an effective checkout process.
While it is true that "reversed stupidity is not intelligence", that does not mean negative examples are without merits.
Someone once said to me "A smart person learns from their mistakes, a brilliant person learns from other people's mistakes."
Positive examples show you what you should do and how you should do it, but they often leave out why. A negative example makes it very clear why you should do things a certain way and avoid doing them other ways.