Simplicity is key, because it is tied up with being fundamental - Harvey Freidman
Now the question really becomes - how simple is simple enough? When we hear some phrase like this, and we don't hear the units of measure of how simple, how to reach simple, then there is only a platitude - no actionable outcomes. How can we measure simplicity? How can we measure the coupling and cohesion of all the parts that make up a simple design, process, or system - to confirm the result is the simplest? How can we learn to ignore the platitudes of those making claims about simple systems are the best when they provide units of measure of the system, simple, or best?
Explanations exist; they have existed for all time; there is always a well-known solution to every human problem — neat, plausible, and wrong. - H.L. Mencken