Saying you don't need snow tires because you have skills is EXACTLY like saying you don't need to sharpen your edges because of your mad skiing skills.
True enough. However, saying that a drivetrain that can only force torque to one tire is sufficient in all conditions purely because you have snow tires is the same thing. It is enough until it isn't, and 'isn't' has very little headroom in a bad storm. AWD will suffer the same fate, because if you can't lock a center differential, or you don't know how to lock the one you have, AWD = 1WD when one tire loses traction.
I drive a truck with front, rear, and center diff selectable lockers precisely because so many people find it agreeable to require near or greater than 100% of their vehicle's capability for conditions that can be regularly expected and encountered. Chaining up in the dark in a storm is IMO one of the most dangerous things you can do when people are sliding off the road and "people" includes large trucks.
The overall point is perfectly well taken - there is no vehicle that will not see an improvement for using the right tires in the right conditions, but "right tire" doesn't have to be a marketed winter tire. I run the same tire year round because it is an exceptional snow tire for Colorado in both packed and deep conditions and does what I want it to do in the summer. It is so good in fact that my wife won't drive our minivan with dedicated winter tires because she has slid around too much in the van and never in the truck.
There is no better litmus test, because the second most dangerous thing to chaining up in the dark in a storm is a wife who is freaking out in the passenger seat.