It's a curious phrase - capturing our bias and explaining our assumptions.
If we know something, that makes it important enough (to us) to know.
We can either assume others also know important things (the things we know) and talk to them in our jargon and metrics and righteous indignation we now assume all caring, knowledgable people feel.
Or, we can make it our purpose in life to explain what's important to those too slow to realize what we've already realized - that what we know makes all the difference in the world.
This is the curse of knowledge... now what to do about it...