Are we building systems we don’t fully understand?

Lately I have been wondering something slightly uncomfortable

Are we sometimes pretending to understand the systems we build the code we write or generate?

With modern stacks layered on abstractions, frameworks, distributed systems, pre trained models, AI generated code It is possible to ship complex products without deeply understanding every component really.

Is this just the natural evolution of abstraction in engineering?
Or is something different happening now?

I was like at what point does “good enough understanding” become acceptable?

Curious how others think about this especially those working close to ML systems or infrastructure.