There is also less physical room for growth.
Tons of infrastructure yet to be built down in the A and much bigger gains to make on land when that happens given the lower COL.
Throw in COL + job diversity + culture + entrepreneurship and it really isn't close.
I dont know much about their burbs but when I was in DC for Christmas my girls brother stays in the burbs and it seemed disconnected from DC compared to say ATL where being in 20-30 minutes away from City Limits you don't feel that disconnected. I know there are other areas in the DMV that have central business districts but once again they all deal with Government, and imo not having a diverse economy is not good at all. DC seems like a city where people brag about having good jobs (all in 1 sector pretty much) while a City like ATL you have high earning people in a wide range of areas. DC is like Silicon Valley to me where if anything happens to their bread and butter industry (Govt for DC, Tech for SV) the whole city is in shambles.