I'm curious why that comparison is more interesting to you? I can see great value in having both data points when trying to formulate a hypothesis about what causes the decline in gut-microbes in us city folks, but I find it hard to think of a use-case for solely a urban/rural comparison without other context.

(Update: I was thinking about this from a scientific perspective, ignoring the idea that people might be interested in what it means for them personally (facepalm) )