C-3PO makes me laugh because you have to remember he was assembled by a child out of things from a scrap heap. Everything about him makes sense if you bear that in mind. Anakin wanted a droid who could help his mother, but the only AI package he could find was one somebody threw out for being too fussy. The combination of tweaking to give him a worried/caring personality makes him constantly anxious. A protocol droid comes with a fair amount of language packages, but why stop there? Somebody threw out like, three different galactic language dictionaries because they weren’t the recent edition. Just load ‘em all up. all of them, even the packs that contain things like ewok and a thousand variants of different manufacturers’ droid codecs. don’t add half the other requirements most legal protocol droids have included at the factory like emergency wipe protocols or shutdown failsafes, or programmed obsolescence. Build that sucker out of non-commercial materials that are already over a hundred years old and still good, tweak it to withstand tatooine of all places.
so now you have this droid that is over thirty years old and it could never be obsolete because it was never manufactured by anybody but a kid on a sand ball somewhere, it’s never running down because it was built to last on tatooine and there’s nothing programmed in to try and urge you to buy the latest model because there is no latest model. 3P0 is simultaneously totally useless yet hyper functional because he was not made according to any specs except “the best most toughest things possible to help my mom for a long long time on a hot desert planet”