Was looking through my office window at the data closet and (due to angle, objects, field of view) could only see one server light cluster out of the 6 racks full. And thought it would be nice to scale everything down to 2U. Then day-dreamed about a future where a warehouse data center was reduced to a single hypercube sitting alone in the vast darkness.
Which means it doesn’t seem like the limit has been hit yet. For standard devices, the general market has not moved to the current physical limitations