I didn't study CS, rather physics, and I find I know far more about "how it works" than most CS graduates I encounter and/or hire.

The reason is straightforward enough - I was a kid, and am now an adult, who cannot stop asking "why?", and habitually disassembled machines to understand them (and then usually hastily reassembled upon hearing the crunch of parental tyres on gravel). Having access to Brittanica as a kid helped too. I started making useful analogue circuits before I even knew ohm's law, as I could see and grok what components did when put together. Nothing beats reverse engineering as a learning experience, apart from perhaps forwards engineering.

Essentially, to have deep knowledge of something requires a desire to have that deep knowledge. Most are willing to stop at some level of abstraction and accept that things "just are", but others, myself included, need to understand how electrons work, why P-N junctions do what they do, what is this matter/energy thing anyway, or how about that spacetime thing that it sits within?

Turtles all the way down.