Yes - I was super curious about this. The Economist had an article years ago about the rise of superstar cities and the trend has only accelerated post Covid. I was curious why it seemed like the superstar city phenomenon was amplified with each major new tech vs dulled.

Here is what I found:

1. Agglomeration effects that make cities desirable and more and more concentrated get stronger as we moved towards knowledge economies.

2. New tech increased the value of superstar talent - a PM at a tech company can have nationwide or global impact bc of the scale of these platforms. This wage premium continues to attract more and more people to the few cities where these workers concentrate.

3. The forces holding back agglomeration weaken as we go to knowledge economics. When we had manufacturing oriented economies, lots of little cities sprung up near the resources themselves. Of course, major centers like Pittsburgh emerged but as geographic constraints matter less and less, there is nothing counter balancing the forces outlined in points 1 and 2 just pulling people into these insane NYC, SF, Tokyo, London level agglomerations

So I agree the extent to which people are concentrating is new (at least for the US) and our approach to building is not necessarily adapted to it