That's because the premise of the article is completely wrong. There's a venerable tradition on Wall Street of generating unmaintainable code and not sharing your knowledge with anyone else. If you're lucky enough for the code you're writing to be mission-critical, you can write your own check and never get fired.
I won't say which, but one of my previous employers had a policy of only using frameworks and libraries that were invented at the org to reduce the likelihood of employees developing transferable skills. I learned about the policy after I wrote a detailed write-up of a specific bug class that was affecting all of our apps, and recommending switching libraries, and sent it to the leads of all of the development teams across the org. Learning this was a contributing factor in my leaving the place :/
