It ships with additional tooling around building and submitting your app to app stores, running your app while in development on your phone deployed via qr code, and a web based playground for quick prototyping and collaboration with others like a stackblitz type thing. It also comes with a number of apis for accessing the native maps, notifications, camera and gyroscope and other sensors, surface to draw with openGL/Skia and honestly a ton more.
I don’t know why you wouldn’t use expo if you are using react native. I’d feel like you were missing out on a lot