So there are additional parameters to being uke or nage then, maybe, other than being held?
Yeah, there's being jumped on, thrown at, fly kicked...and on and on. But all irrelevant to what I said. All exists in static. Hold properly. Actively. It's all there right where you are.
There are many 'perameters' and many principles, but there you are, willing and able to be both uke and nage.