Story says they're power limited. That's half-true. Actually they're water-limited. To generate power, you need water. To cool chips, you need water. If you try to use less water on one side, you need more water on the other side (it's physics ya'll, making and using energy generates heat which requires dissipation). The world's freshwater is diminishing while also being consumed at an alarming rate. The future AI oligarchs are whoever controls the most water.

The other side of the conversation is the idea that large models in DCs on custom silicon is the future. Maybe for enterprise? But consumers will eventually (10 yrs) have affordable hardware designed to run crazy-good local models (more RAM + higher bandwidth). That will take pressure off of datacenters, but also reduce AI profits, and move that money to consumer chip/device makers. Apple is once again the biggest winner. Nvidia consumer chips might get cheaper, but nerfed, to encourage datacenter use where they make more money. I'm hoping AMD can stop being terrible at software so that when we finally have their better hardware we can actually use it.

For datacenters specifically I've never understood what specifically consumes the water. Arent the water-cooling loops closed, so the water just cycles around and around and around?

This only makes sense if you never looked at comparative water usage rates and available water.