This! (not on the not taking you seriously, more on the horses for courses thing)
One of the points to consider is that regardless of how it's powered, an SUV will use X% more energy than a normal format car of the same space/performance/whatever. (That X% is not small, like 20% or so but I can't remember details)
In the UK we've movements towards EVs and towards smaller and more efficient petrol cars, PHEVs etc. These have all brought our car-related emissions down. We've also seen a constant rise in people buying SUVs over normal cars. In emissions impact terms the recent increase from the relentless rise in SUVs has been greater than the decreases from all these other good changes put together. Adds a bit of perspective I think.
Another point I'd add is around cost. Not much point just comparing buy price. You need to add in servicing, fuel etc at the outset. Rather than considering two same purchase price cars and then considering running costs separately, you need to bring the whole lot in at the same time. Once you do this, over any given period of ownership a Range Rover is going to cost a lot more per mile. I suspect it'll cost a lot more per mile even than a Model X. An anecdote: my Dad has an old subaru Forester; pretty much everything about that would cost a fraction of a RR, yet per mile it costs more to own and run than my Model S.
Finally the practicalities of EV ownership. Its not hard but you've got to get your head round a change. Basically you need to want to do it. Nearly all the time you'll charge at home. Range is an issue on days you need all of it, then you have to charge on the road, which means planning ahead, usually requiring about 1 minute of your time, and say a 15-45 minute charging stop which you make use of by eating/working/walking the dog/whatever. Most of us posting on here find ourselves rolling our eyes at motoring journalists getting themselves in bother over this, but then we want it to work, and they want it not to. Or at least they're quite wedded to a way of using the car which has to change for an EV. For me the change isn't an inconvenience really, but it's certainly a change.
On seats, if you need more than 5 you need an X, or to wait for a Y. A new Y, when they come out, would be cheaper to buy and own than your 2nd hand RR, most certainly, but they won't exist in the UK for a year or two I guess.
Why RR Sport? Performance? If it's about that you'll get a pleasant surprise with any tesla.