[diminium]

"I guess the point I am getting at with all of this, is that perhaps we should all try a bit harder to try to understand what's really going on when we use those libraries and abstractions we have come to embrace so much."

The answer to the question is "follow the money".

People don't get paid to learn the inner workings of something. They get paid to do stuff that produces results even if they do it in the worst possible way. Except for a rare few companies (who usually are very good at what they do but are rare), the incentive to make things better does not exist.

The short and even medium term payout of deeply learning the inner workings of something is very small. The people who decided that are the ones with the cash and cash is what most people follow.