I don't follow this one. Is this just making the argument-by-definition that an omniscient being couldn't be curious?

I think XiXiDu is actually saying that if you model a given human, but with changed context that flows from their inferred values (smarter, more the people we wished we were, etc...) you will wind up with a model of a completely different human whose values are not coherent with those of the source human, because our context is extremely important in determining what we think, know, want, and value.