Why is it that people say doctors have an extensive and absolute knowledge of the human body and how it works, but somehow cant explain it when doctors keep miss diagnosing shit constantly or have 90% of the diseases labeled as "cause for disease/illness/deformity is unknown"?

I can open up either a textbook or an online collection of various diseases and all of them (the ones not caused by infections or obvious trauma) will just have the same meme responses
>smoking
>alcohol
>drugs
And ofcourse, if a person does none of those, it goes back to what "quantum physics" is for physics, which is
>genes

It feels like disease and various illness treatment is lagging behind like crazy. Shiny new machine, the same old random guess work and butchering.