Steps to repro:

1. Use attached repro project, ensure that scripting backend set to Mono
2. Build and run it on the device
3. On app start you should see smth like "4-26 19:36:56.862 I/Unity (20466): Printed from Asset_Scripts_FreeLookCam.cs script copy" and this is correct as it was printed from script, used in the scene
4. Switch backend to IL2CPP
5. Build and run it on the device
6. On app start you won't see expected message "4-26 19:36:56.862 I/Unity (20466): Printed from Asset_Scripts_FreeLookCam.cs script copy", as initial copy of FreeLookCam.cs is used. Despite it is not actually used in the scene.