Outside of democrats delusions how can DC even be considered a candidate for statehood ?
It can’t. But the whole idea of a federal district is now obsolete. As strange as this might seem given the modern balance of power between the states and the federal government, one thing that the Founders feared was that if the federal government were located in a large, powerful state (which would have been likely since those states were the most influential), that state might have been able to intimidate and corrupt the new, weaker federal government. A state such as Virginia or New York would have had more of a financial base and a larger armed force than the federal government at the time, so this fear was not unreasonable. The Founders therefore gave the Feds a geographical territory over which it was sovereign and the ability to raise troops to defend it.
Obviously the power balance has now shifted, and the Founders never really envisioned that the capital would become a major city with more than a half million permanent residents. Those residents should be represented in Congress. The best solution IMO would be to retrocede DC back to Maryland. All the citizens of DC would then be represented. All government facilities could remain federal property within Maryland (much like some of the agencies that are already located in Maryland in the DC suburbs).
D.C. being kind of a special case, I would not think could even be considered for statehood. No one in their right mind would want it to be considered, either. Puerto Rico would just likely be another debt we’d have to worry about. Would not be any use to the U.S. as a state as far as I can see.