Humans are creatures which bridge the physical and non-physical sides of reality. Unfortunately for we Westerners (and, via our invasion of every other culture, everyone else now too), we have cultivated and inculcated a way of seeing (or, more accurately, not seeing) without reference to the unseen. In other words, we have deliberately forsaken Insight, the very human and precious ability to See In. Thus, we have crippled our humanity.
Solomon-Kohelet does not defend the Creator, even though he continually acknowledges Him/Her. Instead, he observes (very dispassionately, like a modern social scientist) the world as it is with all its apparently random outcomes. The “good and just” sometimes suffer evil and calamity in the same way as fools and criminals; the unjust and wicked too often seem to live easy, fat, comfortable lives while the innocent, the good, and the just suffer. He never facilely resorts to blaming God for this state of affairs, nor does he ever mention a ‘devil’, a demon, or any other supernatural entity as an instigator; such things just are. But he still has something to say as to why they are as they are, and his insights are right on target to this day.