In both Legends AND the new Disney canon, the original components of C-3PO (his droid brain, frame, etc.) were nearly 100 years old by the time Anakin Skywalker found him prior to Episode I. The Millennium Falcon, on the other hand, was constructed nearly 60 years later. In Legends continuity, the origins of both droid and ship were known prior to the reboot despite C-3PO having his mind wiped in Episode III. In Legends, there are several cases where the droid wonders why Han even bothers with the Falcon instead of simply replacing it with a newer model. Not sure if this still occurs in the new EU - I'm a little behind on that one.
Why would C-3PO agree with other characters that the ship - which is 50 years younger then him - to be "old", "ancient", or "obsolete" as is often mentioned?
I'll accept an answer from either continuity if appropriate.