The sample Photos app: https://developer.apple.com/library/prerelease/content/samplecode/UsingPhotosFramework/Introduction/Intro.html that's updated for tvOS runs fine on an actual device but not on a simulator. In fact, I can't get a simple test app that registers/unregisters for PhotoLibrary changes running on a simulator.
I'm wondering if this is related to the tvOS simulator not having a Photos.app there by default as is the case for the iOS simulator. Any thoughts?