When I needed to go to the airport from Crystal City, I used to walk the trail partway until I was across the highway, then cut across an access road and a parking lot. I could walk from the VRE station to the airport terminal in about ten minutes.
When VRE had a presentation at the Crystal City station about plans for a new Crystal City station, I pointed out that the airport is so close but has roundabout trail access, and that a good pedestrian connection between the station and the airport was needed. Somebody from VRE told me that it was not VRE's problem: VRE was responsible only for the station. I wasn't suggesting that VRE should create the connection.
This reminds me of a transportation conference in Virginia that I attended many years ago. The state was going to require that all new transportation projects that cross another mode of transportation establish connectivity. I cynically thought that people creating transportation projects would avoid situations that would demand an intermodal connection. Well, at least the pedestrian connection construction is expected to begin construction a few years from now.