The frame isn't stainless, just the outer panels. The back side of those is mild steel. Though the doors and tailgate is all stainless. The internal frame is aluminum, with some high strength steel is strategic spots for crash protection. The high strength steel might be the only thing that makes a difference to emergency extraction tools. Before that arrives, hit the door with a sledgehammer, and then throw a 3 inch ball bearing through the window.
I read a safety report that they are finding guard rails alongside the roads aren't designed for heavier vehicles, like the 6,000+ pound Cyber Truck and some are going all the way through them....wouldn't be good on, say, a mountain pass road with a 2,000 foot drop off!!! And they are NOT a truck...I've seen a couple of them, now, here in Colorado.