Movie/video game composers aren't willing to go the extra mile to get out of the swamp that is the early/mid Romanticism idea. That's because it's easy to listen to and The Masses(tm) don't like music that is hard to listen to (like this
https://www.youtube.com/watch?v=KsIATAaR-X0 or even this
https://www.youtube.com/watch?v=lWotpIy0uTg and these aren't the most "out there" examples of 20th century music). They don't like it because they don't understand it and it makes them feel inferior. That's why movie composers regurgitate Renaissance voice-leading with Classical tonality and most of them sound the same. Renaissance music in general is so uniform that you'd think they were living in an Orwellian nightmare (and they were). Horror soundtracks are actually more open-minded and modern than mainstream movie OSTs.
You'd be hard pressed to find a game developer who actually wants modern and professional music. Movies by genius directors (like Stanley Kubrick) are more willing to put serious music in their soundtracks. He used
Also Sprach Zarathustra by Strauss, some pieces by Aram Khachaturian and Ligeti's
Requiem (the Kyrie part -
https://www.youtube.com/watch?v=xdkI49Cvofk) in
2001: A Space Odyssey. I could go on, but the most important part is that game developers (except horror) don't want to use modern music or anything more complicated than what we get. Even late Romanticism music would be fine, even though that movement isn't my favorite. In this context any composer would do, because it is easy.
