Fortunately this is easily disproven, and on my road trip it was abundantly clear that those rated miles click off at 230Wh/rmi as displayed on the trip meter in my AWD Performance. There is absolutely no evidence whatsoever that it depends in any significant way on driving style or average consumption.
Anyone can do the same experiment themselves and prove to themselves that this range is absolutely not affected by driving style. It's quite straightforward! You definitely don't have to take my word for it or get confused by TeslaFi or Stats data - or what the service centers say. It's totally empirically provable.
Here's a quick trip summary (I might type up something more detailed at some point) proving that it has nothing to do with average consumption. You can derive the same ~230Wh/rmi constant from the results for two dramatically different (250Wh/mi and 330Wh/mi) average consumption trip segments. (The constant will be different for other vehicle types - it's the same for all AWD Model 3s though.)
Trip summary
593.2mi/650rmi*251Wh/mi = 229Wh/rmi (trip meter Wh)
583mi/843rmi*332Wh/mi = 230Wh/rmi (trip meter Wh)
It's 245Wh/rmi for charging. That's another even easier way to see that the range indicator has nothing to do with driving style - just look at the charging screen results and swap between miles & %, and read off the miles added and the kWh added. It'll always be 245Wh per rated mile added, after excluding rounding errors on the kWh (for the AWD).