I think you’re absolutely correct, but I think the difference between “Home alone today” vs “Save private Ryan today” is, that when thinking about home alone, because the story is essentially time/context agnostic, they might imagine in being today, but in the save private Ryan it is specifically refering to 2nd world war, so noone would think about it being placed in today’s world But yeah, I agree with you. I could totally imagine a big movie creator lobbying government(s) to hamper war-ending efforts, so they can film there authentically, if it was easier than to do it in a studio
IIRC if DC became a state, only specific federal buildings, such as the white house, scotus & the capitol buildings would remain as a territory (due to the constitution), but, because of a amendment to the us constitution giving DC the same amount of voters _(members of the electoral college)_for the president as the lowest-representation (essentially always 3), which only citizens living inside the area would be allowed to vote for, only the citizens of white house would be able to vote for 3 whole electors.
I might be incirrect, as I am not a US citizen, but I’ve seen this mentioned somewhere long ago