not everyone realizes the obvious in the first place, and then to add the element of true ignorance that comes from the loss or lack of knowledge being passed to new generations? it is a valuable thing to provide supportive “setting” and historical framework that doesn’t seem necessarily relevant or “exciting” to the main topic. it’s not “undue exposition,” it is important contextual foundation. there are many things a person may learn when they aren’t fighting the learning. only at some later date do they realize what they have learned when things seem to “come together” and the now latent gathered knowledge is awakened or becomes relevant to the individual’s immediate circumstance/thoughts.