C-3PO Actor Was Unhappy With Last Jedi, and He Had a Pretty Good Reason
Few people were happy with The Last Jedi, and Anthony Daniels, who played C-3PO throughout all mainline Star Wars episodes, was not among them.
"In The Last Jedi I became a table decoration, which I regretted, because Threepio was worth more than that," he told in an interview with Empire.
This sentiment is not uncommon, and not entirely limited to The Last Jedi. While C-3PO was always a comic sidekick, who entertained the audience by his misfortunes more often than he contributed something useful, the complaint that Threepio got relegated to a background element throughout the sequel trilogy is not uncommon.
You really have to dig through the scenes to find one in which his words or actions have any impact, like the moment when he suggests possible existence of natural un-mapped exits from the rebel base on Crait.
And contrary to what Antony Daniels hoped for during the interview above, things did not get better for the poor droid in Episode IX.
Yes, he had a slightly more significant plot role. But everyone was mean to him. The rest of the cast not only clearly didn't like him, but barely even tolerated him. When in the previous movies Threepio said something stupid or annoying, other characters usually ignored him, in RoS they were much more likely to react by insulting him or telling him to shut up, and many of the fans noticed that.
This, together with total absence of hesitation, when the cast found out they had to wipe C-3PO's mind to get what they needed, made the "taking a last look at my friends" scene a total travesty.
All in all, the sequel trilogy was not kind to Threepio.
Then again, R2, the other half of the iconic droid duo, also did essentially nothing for the entire sequel trilogy, despite being immensely useful in both the original Star Wars trilogy and the prequels.
But after all, the droids were legacy characters, and Disney 's treatment of legacy characters was made clear enough by the fact that they had actors who played the three main characters of the original saga available and willing to reprise their roles one last time, but made it so that the trio never rejoined on screen.