I think a full deletion is premature. IIRC, we’ve had segments of other NPS roads in the system.
My thinking is that the remaining still-driveable segments are not sufficiently significant to warrant inclusion on their own.
1) a missing gap in an existing system (eg Mammoth Cave, California Routes, Yellowstone)
2) a specific NPS unit for the road (eg Natchez Trace, Blue Ridge, George Washington Memorial and Baltimore-Washington Parkways)
3) a through route linking roads already in (eg Painted Canyon Road)
4) an extension of an existing system into a park
5) roads that seem important enough and link with other roads - even if they dead-end
They don't hit any of the first 4 criteria and while the whole road if available as a thru route is justifiable under criteria 5, its stubs on either end... I don't see how they're "important enough". Neither goes anywhere of particular significance.
That said I am open to keeping the MD piece and the DC piece south of Broad Branch Road if people really want them to stay.