Hello, so sorry for arriving late but I am having the same issue. Here what I can report.
It happen with URP if I bake Lights.
If I delete the baked Lighting everything work in the scope camera.
I dont know if is something about the Ultimate Character Controller/Demo/Overlay UniversalRP shader or Unity itself.
I just deleted the baked lights and made my lights Mixed and rebake lights. It solved the problem but it is not the best option as I need the Lights to be baked for Mobile perform.
Something else.. It is not about the camera looking far or close but I guess is the camera looking forward or up. If the camera is looking down the render texture is not black, if the camera is looking forward the resort if dark.