Early Cybertruck clay prototypes were styled after Chevy's El Camino. Elon Musk deemed a Chevy Silverado-style design for the first electric pickup of Tesla too orthodox and wanted something like the Camino.https://www.notebookcheck.net/Cybertruck-was-first-styled-after-Chevy-El-Camino-as-Tesla-designers-balked-at-Elon-Musk-s-final-shape-and-drafted-their-own.748979.0.html
The end result is that the exoskeleton idea didn't work and got reworked/delayed. The vehicle ended up being more conventional and more structurally related to the other cars in the range. In other words it has all the downsides of a stainless steel exterior for no reason.