Oh don't get me wrong, I'm fully on the side of close convenient access to an airport. I'm done trying to drive 45 min - 1.5 hr just to make it to the airport (ATL, SFO).

I think the factor in play here is that there is a transit system connecting the airport to downtown in a reasonable manner, where as many other places do not have that flexibility of car vs. transit vs. uber/taxi, at least from my personal observations around the country.

This is also a pretty inaccurate way of looking at it. Sure it may be the shortest distance from the geographical center of the city, but that doesn't mean all of these other cities neighborhoods aren't densely populated with sprawl. Take San Diego for example, they cannot expand that airport because the highrise sprawl basically goes right up next to it. Same with HNL and SJC. The list goes on... there are actually very few on that list that if you actually go in and look at their situations individually you'll find they are removed from dense areas (SMF, BWI, AUS, etc.)