This feels like a critique of the metric not of the game. Like be realistic, do you actually think Civ7 is less popular than Revolution right now?
I am not sure. I just went looking for evidence to support or critique the theory that "there was a large exodus of active players from PC to consoles". I was surprised that Civ VII didn't appear anywhere on the Xbox charts actually. Maybe I checked at a non-ideal time.
To provide a little more context Anno 1800, Civ VI, Age of Empires IV, and Stellaris (in that order) appear slightly above Civ Revolutions. Age of Empires 2 and Crusader Kings III appear slightly lower than Revolutions. On the Xbox store Civ VII only has 348 reviews (2.5 stars average) so perhaps it, or strategy games altogether, is/are less popular on the Xbox ecosystem.