The answer is simple. Because these institutions support American culture in general and silent film in particular through their coverage of the arts and through modest financial support in the form of grants.
A few specific examples.... On a handful of occasions, National Public Radio stations have broadcast stories about Louise Brooks and her films, and on a couple of occasions, I have been a guest on various NPR stations around the country talking about the actress. Would that happen on mainstream media? Unlikely. (Or in other words, would a media/entertainment landscape dominated by asinine shows like "The Apprentice" and their ilk ever consider anything like silent film. The answer is again NO.)
It's patriotic to support PBS, NPR, the NEH and the arts.
Here are a couple instances when NPR covered Louise Brooks:
Cone, Nathan. "After Wings, Hollywood's Wellman Rode The Rails For Beggars Of Life." Texas Public Radio, August 16, 2017.
-- a review of the Louise Brooks' film
Mack, Megan. "Connections: The Rise, Fall, and Resurrection of Louise Brooks." WXXI, December 2, 2015.
-- hour long program with film critic Jack Garner, documentary filmmaker Charlotte Siller, and Thomas Gladysz, director of the Louise Brooks Society
Later this year, PBS Masterpiece will broadcast a film version of Laura Moriarty's The Chaperone, the story of the summer Louise Brooks' left home to study dance in New York City in the company of a chaperone. Would mainstream media make a film about such an "obscure" subject? Again, it's very unlikely.
Not convinced on the need to act? Be sure and check out this Publisher's Weekly article, "Trump Renews Bid to Eliminate Library Funding, NEA, and NEH".
Show your support of these institutions by speaking out against budget cuts. Learn more at Protect My Public Media. And act. Sign a petition. Send an email. I did. Let your voice be heard.