> You must understand why you damaged your system and why the fix you applied fixed it.
Only GNU/Linux (in fact any free software) gives you the possibility to fully understand your system. It allows you to drill down to any level required. Thriving for such understanding is a trait of hackers, but having the freedom to do so is beneficial for any software developer- at whom the article was targeted.
Most of the time I would rather have devs spending time to learn their database engine for back end. For front end devs would rather that they spend time understanding how web browsers work.
While I like to spend time getting to know OS details and running windows or Linux servers - for instance I do get a grasp of CSS and can use dev tools in browser, but I see how a front end developer fixes CSS issues in 5 mins that take me 30mins.
We cannot expect everyone to know everything - but also I think we can expect some basic knowledge of different parts of stack.
Not really, sadly. There's a bunch of binary blobs for the CPU as well as other opaque firmwares in the hardware.