We need a term to describe the delusion humans have thinking that their mind is the most complex thing in the universe. I googled this and it spat out Anthropocentrism, but that isn't right (I don't fault people for the belief that humans are the most important thing ever; seems reasonable considering the circumstances). I don't feel like making a new term right now. A corollary is the delusion that clams don't have emotions. Clams sure do have emotions. Let's move on.
We tend to think some things are less complicated because we understand them. Understanding to most people means breaking things into ever smaller pieces and being able to predict their function. To the majority of the population who aren't real scientists, however, understanding means you can answer a question with words that others will nod their heads to in agreement. You need only walk around with a 3 year old, and on maybe your 3rd or 4th why, you will realize how little you understand (and it is an additional clue that the 3 year old also won't be particularly in awe of your brilliant explanations).
It is a mistake to assume that because we don't understand how something works, that that thing is very complicated, and vice versa. Our perception of reality is so amazingly minuscule that we are literally blind to anything outside of it. I wouldn't exactly say that reality is necessarily complicated or unknowable (to us, perhaps it always will be), but given that the universe is full of self similar processes, it would be foolish to assume that everything is not intimately connected, or relatedly that some things make perfect sense but others do not. Again, that feeling would be a clue to our misunderstanding.
This is very semantic, I understand. Understanding our human-scale reality is obviously important to improving our everyday lives, and we are grateful to the people who devote their time to small facets of this task that collectively make each subsequent human more well-off. (It is debatable that we are all more well-off, but that is a separate philosophical topic). I do not think we should all throw our hands in the air and give up working on chipping away at the problem (is it really a problem?). I do think that the average person needs to embrace uncertainty and focus on what brings them joy, rather than be distracted by simulacra (digital abstraction disease, etc. This is not a new thought even if I give it a new name. If you haven't noticed, every religious, spiritual, enlightened, wizened person keeps saying the same things throughout our recorded history).