If Elon would have looked back, he would have seen that Delorean has already tried bare metal, and it's nearly impossible to fix. Dent your truck? May as well paint it.
I mean, Elon obviously doesn't care about repairability, but the first few fender benders will result in a pile of articles about how unfixable the body panels actually are.
But at least John DeLorean didn't demand that the parts be accurate to within a few microns. Maybe he was too busy making cocaine deals to do it, but still...