Goodmorning - perhaps the flood gates will now open.
I think its partly due to our Rhino user base not being so vast, and somewhat segmented in terms of industries they span.
But, by the same token, we could again ask why is Rhino itself not natively supporting IES, if Rhino users require it so much?
Sure, VRay has up to now covered most use cases.
It's added now as a Feature Request though. I can only suggest that other Rhino users who want this feature now speak up so it has some chance of being looked at.