Well done on the research. Most miss these numbers. if you have the large pioneer rack the off-road ratings drops to 126lbs.Apology, my numbers were slightly off. I was recalling them from memory.
According to this: https://www.rhinoadventuregear.com/...-jl-4dr-hardtop-3-base?variant=29382775603318
the off-road capacity is 130lbs dynamic, 190lbs dynamic on-road.
I see 200lb tents strapped to these backbone systems in videos all the time.