I actually have Tim Sheppards book. The problem there is that it was written in 1993 when none of these things existed. The Defender and D1 are relatively crude, ponderous things, and their, mass and architecture to indeed put them at some disadvantage when stopping (not necessarily when steering). However, the state of the art has moved on greatly in 3 decades and such vehicles now have the benefit of systems that were not available then. What may have had a grain of truth 3 decades ago is no longer valid.
A car that can selectively drive individual wheels, can selectively brake individual wheels, can alter steering weight on the fly, and that can even (on some really modern tin like the current XC90) actively alter damping and spring rates on individual corners of the vehicle stop and corner in the snow better than one that cannot do those things. There is no two ways about it. Even on my old bucket, the stability systems are such that it is almost impossible to overturn an XC90, wet or dry - sadly not true of, say, a Corsa or Micra.
I live next to a forest, and when it snows plenty of cars end up in ditches. Theyre always FWD hatchmobiles with the occasional 3 series thrown in for variety. Never a proper SUV. Indeed, my step brother regularly patrols in his Shogun and charges the hapless drivers 50 quid to tow them out. So not only can normie drivers not go round corners in those conditions, but they have to rely on an SUV to rescue them.
But as you say, appropriate tyres and a driver with half a braincell. Even the best equipped SUV won't save the proverbial Roger Ramjet from his own idiocy.
The one inescapable truth is that, according to Thatcham Research, no one has every been recorded in the UK as having died while travelling in an XC90. Not ever. Not wet, dry, rain, snow, wind or ice. Next up is the Audi Q7, which has half a dozen model years for which the same is true. Pretty sure they're both large SUV's