The Washington Orange line along the I-66 median is basically how modern rail has to be built, but at the same time, any rail system nowadays can’t be successful if it’s built with the idea that everyone wants to go downtown.

You can find early NYC subway pictures of the end of the line in the early 20th Century looking like someplace 50 miles out in the country, so the development pre-WW II followed the rail lines. Now the development has grown along the Interstates into and the loops around the city, and in many cases, commercial business have built up on those loops so that people don’t want to go downtown, they want to go from one outer area to another.

That means the feeder roads also have been developed to get large amounts of people to and from those main highways, and that’s where the stations (and the parking garages) have to be, and the lines have to link for transfers in places besides the central city hub. Mass transit systems that force you to go downtown and then back out again to get from one outer area development to another isn’t going to have many takers.