He still makes his own stuff though; it’s not like an exclusivity agreement or anything as far as I’m aware, as he’s done music for films like Beyond Stranger Things. I’d recommend looking at his Wikipedia biography and/or discography.
EDIT: Semi-relevant, but I’ve always enjoyed Rust YouTubers who’d actively use music in their videos (such as BlizzardID and his The Power of Music). Ya’know, just in case people thought Minecraft’s ambiance wasn’t enough of an example?