The problem is "extremely limited" is a misnomer. For the X7, I agree. For other luxury SUVs, I disagree,
The G wagon, LX570/200 series, and the Range Rover have anything but 'limited 4wd capabilities'
You can take a previous generation Range Rover Sport right now, bone stock, up and down Wipe Out Hill. Wrangler Rubicon Unlimiteds on 35's scoot down on their sliders like a wounded dog because of the extreme breakover.
Now the advantage of a Wrangler platform is the modifications, but if you can do 5-6 rated trails out of the box on crappy 20" rims...bone stock.....then I would hardly call that "limited off-road capability".
The X7 in the OP isn't good at all. I'd disqualify it based off of gearbox alone. I would argue against lumping all luxury SUV's in that category though. The following 2018 models have incredible off-road capability:
G Wagon
LX570/200 series
GX470
4Runner
Range Rover
Range Rover Sport
Disco 5 HD
And the next batch has "servicable" off road capabilities:
Grand Cherokee Trailhawk WK2
Mercedes Benz GLE or whatever it was that's off the WK2 platform
Tahoe
Expedition