Hi, thank you for reporting and voting on this. This is more of a UX and documentation fail rather than a technical limitation, and I'm working on improving these aspects.

Longer explanation:

The culling mask is an old feature. Lots of customers didn't like light.cullingMask because it checks against the layer of the mesh renderer's gameobject. This is problematic because the layer also controls other aspects, such as physics. So it's annoying to couple lighting and physics in this way. Another limitation is that a gameobject can only be on one layer at a time.

The newer iteration of the same features is called Rendering Layers. The way it works is that you turn on the Lighting -> Use Rendering Layers setting on the URP asset. Then you set the Rendering Layers on the Light. Finally, you set the Additional Settings -> Rendering Layer Mask on the Mesh Renderer. This decouples the lighting from the gameobject layers and other Unity systems. A mesh renderer can also be on multiple rendering layers at the same time, so you can also achieve more complex lighting scenarios this way.

Rendering Layers are more powerful than the culling mask, and work across Forward, Forward+ and Deferred. In my opinion, you should always use Rendering Layers instead of the Culling Mask, which we cannot remove because of backward compatibility.

The feature is currently not exposed in UI in the best way possible, and has led to confusion. I'm fixing this in 2023.3, 2023.2, and 2022.3, with better tooltips, warnings, inspectors, and docs.