And yes, the title isn't hyperbole. You can skim the parts describing specific tooling, but the fact that the description of the memory hierarchy and how it works hasn't been internalized by every programmer is a travesty.
I, honestly, don't know if it will help me in terms of my career because at my current job, it's not something I can put to use. However, I want to learn this because it is fun (for me) to understand things close-to-the-metal.
Jokes aside, the guy asked how it's been useful and it's not terribly convincing that your first (and only?) thought was interview questions.