wasn't pudding set up for traitor from very beginning in whole cake island arc? During that arc didn't we learn about her race can read poneglyphs as well? It's not just robin who is going be target. Their other methods that people can use to get to laugh tale. Pekcoms had said, way back in zou if sanji had married pudding the strawhats would be part of the big mom pirate’s crew. Which Luffy himself refuse. Pudding had shown no interest going on adventure and seeing the world. She wishes to be love by another person because her family didn't give to her. Sanji had to charm her get her on our side. We already have member grand fleet who represents the giant race already. By the end of wano Luffy's crew would already be fully complete by then. Yamato didn't betray Luffy. She at least did something important rather than staying on side lines and her fight wasn't completely skip over unlike vegetable who staying in the grass right now.