when stripped of paint, have some ugly surprises like greenish panels.
primer .. more a surprise and worry if it's not there ..
With 2024 clad sheet having a thin outside surface of relatively pure aluminum, I don't think corrosion is a huge problem,
gives some cathodic protection but only if you don't scratch the surface .. so, what do we do ? .. we drill lots and lots of holes in the sheet ... the reality out in the dirty world is that corrosion of skins and such is a MAJOR problem, takes a lot of resources to be thrown at it, and is a right pain.
For interest the link is to a general
Data Sheet from Alcoa.
The clad surfaces themselves are oxidised .. aluminium oxidises (corrodes) fairly readily. However, like any cathodic protection system, if you can keep the mechanicals OK, and the clad layer intact, you can do a good job of thwarting Mother Nature's endeavours to bring you unstuck with corrosion ...
and it sure seems like skin inspections would be easier w/o paint.
that's true enough .. but I suggest the main interest is weight saving and, for AA, brand differentiation.