I've had a dozen rigs that have been lifted and locked. Upwards of 37" tires on several of them.I do agree with that statement. Just speculating about it. seems nobody has tried to make a bigger lift(than the spacer lift) but alot of people want one.
I figured I'd do something wild when I bought my Cayenne 8 years ago. That was until I started using it. I have a 32" tall tire on it and I can still beat more than half the field at a Porsche club autocross and tow 7700lbs better than any other tow rig I've owned(including quad cab duallies).
The thing is simply a freak of nature. If it were any other luxury SUV I'd have it sitting on 35s a long time ago