They'd understand SO much if they just took the evidence all around them seriously, the death and disease they think are normal, that are really evidence of the fallen state of the world.
You seem to forget, though, that at one time that
was taken as the framework with which we viewed the world, with the result that we
didn't understand anything.
I mean, you're sitting here saying "gosh, things would be so great if only scientists took genesis literally, we'd understand so much" butm being completely ignorant of history, you're ignoring the fact that for
one thousand years we operated from those assumptions, with the end result that human technological progess was halted for centuries.
A likely story.
It is, indeed, the most likely explanation.