Vehicle bodies are made of several layers of sheetmetal consisting of at least an interior wall and an exterior wall and sometimes another wall in between for more structure. When repairing the body it may be required to repair all of the layers not just the exterior layer.
Never dig into the body of a 45 year old car unless you are willing to fix the horrors it may expose. A small amount of rust or a repaint can’t hide the true degraded condition of what lies beneath.
Just because the Tesla is made in America it doesn’t mean every body shop is willing to work on them when they need some repair. This 2014 Tesla Model S is a couple years old and ready for a refresh from all of the road rash.