Nohow, because the real world is informal. This is as far as coding can and will ever go, basically.

And like yes, it does just launder defects to a layer higher, but another way to phrase that in this case (and in many other cases) is that it raises the bar.

Instead of defects being mostly about nonsense minutia (relative to business logic), they are about actual design decisions and their correspondence to reality, i.e. the actual original goal and point of this god forsaken, navel-gazing field.