I think one would need both cameras shooting at the same scene at the same time of day to really determine that.
I could do 1600 without much of a problem with my 7100 if the light is bright enough and not have to do much cropping, where as a 7200 would look worse at the same ISO shotting in low light with a dark subject.
That's exactly what i'm finding. Iso 2000 can have stunning image quality and then a few clouds can move in or shoot in shade and iso 100 can look terrible in comparison.