Conventional logic would say that having the five best defenders on the court would result in the best defensive outcome.
When there’s no weak link on the defensive end, the offense doesn’t see any mismatches on the court and is therefore unable to take advantage via switching, which should work out in the defense’s favor.
This is part of what made Boston’s defense so dominant last season. With a plethora of quick and strong perimeter defenders and a front line of versatile big men, the Celtics had no single player that could be targeted defensively (ok, maybe Payton Pritchard at times).