I'm not sure about it being overstated for those who sail in areas with mud bottoms. I've heard quite a few say that they got stuck and could only get free with help. I suppose sand won't create that same suction that mud would.
I would think heeling the boat over to get unstuck wouldn't work with a wing keel. It would just dig that edge in more. OTOH, if you wanted to dry her out in tidal conditions, it would probably sit on the wing nicely.