https://www.gamespot.com/articles/fallout-76-heres-the-main-theme/1100-6462365/

Fallout 76 has based its marketing around its unique setting in West Virginia, including a debut trailer with the famous folk song and state song "Take Me Home Country Roads" by John Denver. As the release draws closer, Bethesda has now released its main theme, from longtime composer Inon Zur.

The track isn't "Country Roads," but Bethesda does say the score is "inspired by the beauty of West Virginia." Zur has previously composed for Fallout 4, Prince of Persia, Dragon Age 2, and many more games.