... I have never once ever been in a situation where I thought AWD would have gotten me out of a situation that my RWD wouldn't have. Not once, and I do a lot of winter driving.
Obviously this will vary considerably depending on where you drive.
I have had a few (very few but still) instances where my RWD P85 would get bogged down in thicker snow, and the TC became counter-productive by cutting power so much I almost became immobile (once even on a slight downhill grade!). My worst such event occurred while going up a short slushy hill, where I learned the sweaty way that you cannot disable TC while pressing on the accelerator (and while praying to god the car does not stop and start skidding backward or sideways). I was lucky and SLOWLY crept to the crest of the hill (with cars all around me), but it was close, and nerve-wracking. Lesson learned, if TC must be disabled in winter - not a great idea in such a powerful RWD car - in can only be done with foot off the accelerator and pressing the brake pedal.
The flip side of this issue occurred on another small hill in front of the old Royal Victoria Hospital in Montreal (on Pine Avenue for those who know the area). This is a high-traffic street where the city did not always clear snow quickly enough, and again slush accumulated (moderate amounts of heavy salt-laden mush). Having learned from the above experience, I disabled TC while stopped at the light before the hill, and gingerly feathered the accelerator on the way up, with significant fishtailing of my rear end. Not fun, again got lucky - did not hit anything and made it to work. Other vehicles were also struggling that time, except for those with AWD.
I run Nokian Hakka 7s, and also have years of winter driving experience, but on subsequent days like that I seriously debated taking the S.
In both of those situations, I am certain that having a D variant would have greatly reduced, if not eliminated the issue (they did not exist then, so all I could do was wish). A test drive of a Model X this past weekend in thick slush with freezing rain was impressive enough to me that I placed an order for one (family size prevented me from upgrading my S to a D variant, I needed the large frunk!). Tesla's AWD is really unique on the market, and I have driven the best mechanical variants available over the years (Volvo Haldex, Subaru, and Audi Quattro).
... AWD won't help you stop when you need to!
Totally agree with you.