need to be somewhat close to important population areas
They really don't. I live in regional Australia - the nearest data center is 1300 miles away. It's perfectly fine. I work in tech and we had a small data center (50 servers) in our office with a data center grade fibre link - got rid of it because it was a waste of money. Even comparing 1300 miles of latency to 20 feet of latency wasn't worth it.
To be clear, having 0.1ms of latency was noticeable for some things. But nothing that really matters. And certainly not AI where you're often waiting 5 seconds or even a full minute.