One would think from far away perspective or first principles, that we have passed the point of liquid cooling being way more optimal in the datacenter a long t

One would think from far away perspective or first principles, that we have passed the point of liquid cooling being way more optimal in the datacenter a long time ago already (if you're actually doing computing and not idling). But everything's so slow and path dependent. I wonder how much you could do with a single rack if you got really serious about it. Cooling, power, networking etc.