Yes, the National Park Service shouldn't be paying to maintain major commuter roads and bridges in the DC area

For obvious historical reasons, certain area parkways and bridges were developed by the Federal Government, in this case the National Park Service.

While they are parkways, a road type that is designed to be park like, and are decidedly different from more traditional freeways (Interstates) and regional arterials, many are used as freeways, such as the George Washington Parkway in Virginia, the Suitland Parkway in DC and Maryland, the Baltimore-Washington Parkway in Maryland, and the Clara Barton Parkway in Maryland, along with the Memorial Bridge which crosses the Potomac River connecting the Lincoln Memorial in DC to Arlington Cemetery and the GW Parkway in Virginia.

Mount Vernon Parkway is not so much commuter oriented compared to the others.  It connects to the George Washington plantation, Mount Vernon, in Fairfax County.  But it still serves large residential sections of the county.

I've written about this in terms of the Memorial Bridge, that NPS isn't in the business of providing transportation infrastructure in the DC region, it's a parks organization and that instead of paying to serve commuters -- although my understanding is that Virginia DOT pays some of the cost of maintaining the GW Parkway -- this infrastructure and the cost of maintaining it should be off loaded to the local jurisdictions.

-- "The National Park Service shouldn't be on the hook for basic roadway infrastructure in the Washington Metropolitan Area," 2016

That way they can spend money elsewhere on the maintenance and repair backlog of more than $10+ billion in capital projects and facilities ("National Park Service delayed $11 billion in maintenance," Washington Post), which is only worse now because of the federal shutdown, which accelerated damage and degradation at some parks units.

WAMU/NPR has a story on this in terms of the Baltimore-Washington Parkway ("How did the potholes on the Baltimore-Washington Parkway get this bad?.)

Ryan Zinke is hardly a genius for pointing this out. From the article:

The National Park Service has owned the parkway since it opened in the 1950s.

It was viewed as scenic, wooded entrance into the nation’s capital.

“It was always meant as parkway-type roadway,” said Superintendent Matt Carroll.

But the role of the road has changed, according to former Interior Secretary Ryan Zinke.

“The Department of the Interior is not in the business of managing commuter highways,” Zinke said a news release last June. “We owe it to the 120,000 taxpayers who use the Parkway every day to make the best possible decision to relieve traffic congestion and increase public safety in the region.

While the article doesn't say anything new, it does include a  great drawing of different roadway types, which was produced by the HIstoric American Engineering Record.

It turns out that it's from a set of 51 photos and drawings produced to document the Baltimore-Washington Parkway.  They are pretty cool and worth checking out.