Who have big SUV-s?
I note a conspicuous lack of spacious SUV-s not from USA.
US models:
Cadillac Escalade ESV 566 cm long, 189 cm high
Chevrolet Suburban 565 cm long, 195 cm high
Ford Expedition EL 562 cm long, 197 cm high
Lincoln Navigator L 567 cm long, 199 cm high
But elsewhere, the top models are:
Audi - Q7, just 508 cm long, 174 cm high
BMW - X5, 485 cm long, 178 cm high
Honda - Pilot, 485 cm long, 180 cm high
Infiniti - QX56, 526 cm long, 200 cm high
Lexus - LX, 499 cm long, 192 cm high
Mercedes - GL-class, 508 cm long, 184 cm high
Mitsubishi - Pajero, 490 cm long, 190 cm high
Nissan - Armada, 526 cm long, 200 cm high
Porsche - Cayenne, 480 cm long, 170 cm high
Range Rover - 498 cm high, 190 cm high
Toyota Land Cruiser - 495 cm long, 188 cm high
Volvo XC90 - 481 cm long, 178 cm high
So... how do the interiors compare?
US models:
Cadillac Escalade ESV 566 cm long, 189 cm high
Chevrolet Suburban 565 cm long, 195 cm high
Ford Expedition EL 562 cm long, 197 cm high
Lincoln Navigator L 567 cm long, 199 cm high
But elsewhere, the top models are:
Audi - Q7, just 508 cm long, 174 cm high
BMW - X5, 485 cm long, 178 cm high
Honda - Pilot, 485 cm long, 180 cm high
Infiniti - QX56, 526 cm long, 200 cm high
Lexus - LX, 499 cm long, 192 cm high
Mercedes - GL-class, 508 cm long, 184 cm high
Mitsubishi - Pajero, 490 cm long, 190 cm high
Nissan - Armada, 526 cm long, 200 cm high
Porsche - Cayenne, 480 cm long, 170 cm high
Range Rover - 498 cm high, 190 cm high
Toyota Land Cruiser - 495 cm long, 188 cm high
Volvo XC90 - 481 cm long, 178 cm high
So... how do the interiors compare?

You are asking questions that go way beyond what most of us are interested in when buying a car. Not that I am diminishing you post or interests in any way, but the fact that a Honda Pilot is 2cm taller than a BMW X5 plays no part in the decision making process. A Honda for example is not a BMW and never could be. For a start, the drivers seats on modern cars adjust in so many different directions, providing you are comparing two cars of a similar class, the head room will be pretty much identical. As for the interior, that is going to depend on a lot of things. During my last Summer holiday I had a Jeep Grand Cherokee. Driver and front passenger had lots of room, the boot was huge, but at the expense of the back seats.
Cadillac is owned by GM.