I am using the regular (Shuriken?) particle system for URP. It seems that Light Layers do not have an effect on the particles particle system and are thus lit by every directional light which is currently on in the scene. There is an option in the particle system to select a light layer, but this has no effect. Are particles systems or their material exempt from the Light Layers? Is there a way to easily get this working in URP?
Decided to ditch Shuriken for the VFX Graph system. The Light Layers now work in URP when using the particles.