R2 and 3PO have managed to stick around for 3 generations without an upgrade. It’d be like still using Cray 1s today.
Favorite exchange between those two:
“”Artoo! What are you doing here?” [R2-D2 chatters] “Well, I can see you’re serving drinks, but this place is dangerous.”
Always imagined R2 did his own upgrades every time he hacked into something...sometimes he shared with 3PO but golden boy got tired of the obvious viruses that R2 would add to make him say stupid things.