A folded piece of 20 ga mild steel isn’t necessarily going to be stronger than a flat piece of extra-hard 301 stainless, because there’s a 6 to 10-fold difference in material strength that the geometry may not be able to make up.

“per pound” doesn’t tell the entire story, though. While weight affects a lot of costs (raw material, transport, operating costs), the number of manufacturing operations affects costs as well. Particularly welding and finishing.

Aerodynamics, probably. You standard truck bed is great for reaching over the side, but causes major low reattachment issues. 

They probably get better side impact resistance than your typical car door. Not only resistance to bullets and sledgehammers, which would only happen in weird on-=stage demos, but more importantly resistance to other vehicle impacts.

20 gauge mild steel doesn’t exactly scream “rugged and durable”, though.

If it’s a matte finish, not highly reflective, then the waves won’t really be noticeable at all. And people buying this design probably aren’t the type who critique panel gaps...

I don’t get the “use it as a rover” thing. Flat panels are a terrible design for a pressurized vehicle, and if it’s going to be unpressurized anyway then a tube frame is a lot lighter and stronger than this panel body.

The only materials comparable to hardened 301 stainless in both strength-to-weight ratio, and in cost, are aerospace grade aluminum alloys. Those don’t rust, but they can corrode in a salty environment. 

“Everything else makes sacrifices” ... not everything, though. Extra-full-hard 301 stainless is the strongest metallic material by ultimate tensile strength - approaching 2 gigapascal UTS, about 7x stronger than the mild steel used for auto body panels, and even stronger than tool steel, titanium, and carbon…

Just because Apple has the algorithm that generated the UIDs doesn’t mean they have the UIDs or even a usable subset of them. If they implemented the system properly, only a very small part of the UID is actually UNIQUE (only 30 bits will make 1 billion unique numbers), and the other 225+ bits is RANDOM. There is not…