Well, yes. Permaculture seeks to adopt practices from the kind of long-running success stories you're describing. For historical reasons it does so much more with respect to paleolithic practices than bronze age ones, but there's nothing to permaculture which requires it.

> I'd imagine then that 11,000 years of traditional rice farming in the Yangtze River Valley must have really sucked the life from the soil and there's barely another millennium or two left there.

They have. Traditional farming is very taxing on micronutrients.

China (and Egypt) used a lifehack called "silt". Basically, they use it to periodically replace the topsoil.