There was a period of time, way back when, in which personal computers were relatively common in households, but repair services basically didn’t exist in most places. Computers were still expensive, and not really useful enough that you’d just go buy a new one when it broke, you’d either fix it or hope someone you know could show you how.

That was a time of “learn or don’t use it” (we had a pc we couldn’t use for 6 months until we figured out how to fix it) and it’s sad that it was so short, because only a very specific age group of people grew up with that pioneering mindset. Since then it’s gotten more “user friendly/foolproof” (locked down and hidden) and the knowledge of how to do stuff with it is becoming more rare on the whole.

I always sort of expected that generations younger than mine would be more tech inclined (inner workings, not just using it) but they really aren’t due to how so much of our modern tech is just.. not approachable, locked, or hidden.

The primary reason is that the technology is designed in such a way that large distributed teams of people can build them without anyone needing to understand the entire structure, because the entire structure is beyond the understanding of a single mind.

A software developer wouldn't even try to read all the source code of all the libraries their app relies on, nor the machine operations and logic operations and character encodings and chip design and the chemistry and physics of computation.

We've consciously decided to abstract things down to reliable interfaces, and as long as the thing behind the interface works, we can understand the interface and build on top of it.

These other reasons are secondary to this one: people don't understand fully because we've gone beyond what a human can fully understand, and deliberately and consciously, decided to adopt this system of abstractions and interface contracts to allow ourselves to operate in the space beyond where the human mind can go.