Lighting has always been a bugaboo for me.
Nope it doesn't have to do with culling. However, I'm pretty sure it has to do with distance and therefore dynamic lights must have issues with performance.
It's just that with static wall lights they don't appear to be on with a static light. You have to make the wall light dynamic for it to reflect the static light. If you want the wall light to be static then the light has to be dynamic. Go figure. At least with what I'm finding here. Also, with a dynamic light and a static wall light entity, the lighting is softer. The other way around and the lighting is much harsher. Then with a static light, my "waiting for threads to finish" time has increased tremendously. As most people, I hate to wait. In fact, I'm still waiting while I am writing this post. And waiting . . . and waiting. Never mind. I'll post now. Still waiting.
The past has a lot of memories to hold onto; but, today is chock full of new adventures, and, the future shouts out, "The best is yet to come!" -- TerryC