There are two types of knowledge you can get in IT. Fundamental knowledge that transfers across domains and trivia.
Problems with trivia: - Just like the article pointed out, it often gets outdated. - If the system you work with is well-designed, you don't need to know much trivia about it. - Fundamental knowledge allows you to derive more knowledge. Trivia is gained through rote learning and doesn't allow you to derive anything. - Trivia hinders interoperability and innovation.
Unfortunately, most IT people love their trivia. They brag about knowing trivia. They separate in-group from the out-group by trivia and use that as hiring criteria. Finally, they proudly design systems that require you to learn new trivia.
It's a giant waste of society's resources, but it also creates job security and allows some people get much larger salaries that they would otherwise.
As far as I'm concerned, eliminating the need for knowing trivia about their systems is one of the primary responsibilities of a good software engineer, regardless of specifics of what they do.
"Stop designing frameworks" is my advice.
PS: Design patterns are also trivia. Peter Norvig gad a great set of slides on that. http://www.norvig.com/design-patterns/