scripts/RemoveLights.cs

A sandbox Component named RemoveProps that, on start, recursively traverses the scene graph and destroys any GameObject child that has a Prop component.

Native Interop
using Sandbox;
using System;
public sealed class RemoveProps : Component
{
	protected override void OnStart()
	{
		void Helper( GameObject obj )
		{
			foreach ( var child in obj.Children )
			{
				if ( child.GetComponent<Prop>() != null )
				{
					child.Destroy();
				}
				else
				{
					Helper( child );
				}
			}
		}
		Helper( Scene );
		base.OnStart();
	}
}