There’s a surprisingly straight line from Richard Wagner to modern film music—especially through composers like Erich Wolfgang Korngold and John Williams.
Leitmotifs, massive orchestration, emotional storytelling—it’s all there on the big screen with people who never would go to a classical music concert enjoying orchestral music that would be home in a symphony or opera.
I gave a talk on this (with clips from Vertigo, Citizen Kane, and Star Wars) if anyone wants to go down the rabbit hole of film music that should appeal to people who like classical music.
It's on YouTube at https://www.youtube.com/watch?v=yy-jzIxaBpM
Even Alex Ross was kind enough (along with my mother) to say nice things about this talk, so I’m legally obligated to mention that. And maybe the Wagner family will ask for royalties....