It's still a matter of putting the disc in the drive, rebooting, and following instructions.
And you can pretty much rule out there being factory supplied discs if they're thinking their existing copy is illegal. If the system came with XP, it would have a license for it, and there wouldn't be an issue.
Finally, it wasn't meant as a "slam". It was meant to help keep you from wasting yours, and others, time asking questions that have no bearing on the issue at hand. Your vehicle is out of gas let's say. Does someone asking if its a car, truck or SUV help solve the problem of being out of gas? Or whether it's a 4-cyl, V6 or V8 engine? Does the wheel size make any difference? So, after walking a couple of miles to a gas station, does the clerk asking you this as you pay help you at all?