You answered my unspoken question: "what does the "Use Nodes" setting do?
And I had never heard of IES textures before; every YT tutorial is like "slap an HDRI to anything and there you go," which... okay I guess, but this just takes the scene referred information and the renders to a whole other level.
IES is a relatively new thing in Blender (and by "relatively new", i mean since 2.8, so only the last 6-8 years -- which is a while now I'm saying it, but still feels new to me... :D ) and I think still only works with Cycles (but not Eevee), so it might be something a lot of people aren't really familar with using, but they can help with making the lighting look more correct.