Thats wrong. Sanji knew his crew was about to deal with Kaidou with no coming back and thus he didn't want to burden them with the Shit created by his backstory. Thus he decided to leave the crew to not make them deal with 2 Yonkou at once.
In other words Sanji tried to prevent the situation they are currently in by sacrificing himself.
Actually that is redemption to those scene . Sanji abandoning his crew was because of Zeff but later when reiju told him Baratie pirates were just mere decoy to bring him here then Sanji realized how he cold shoulder some of the responsibility of the crew.
You could look at how angry Nami was when he kicked luffy .
This scene is consistent to Sanji's character he needs to trust his crew to enough and share his burden . Hope you understood what i said . I would say its not bad , Oda will certainly answer this in sbs it might be likely because of the events in WCI , sanji has grown to trust the lower mid trio more now .
Execution is probably terrible , Oda just put him in same situation like Khalifa , viola and pudding . Maybe it would have been better if these scenes were not during war arc my two cents because we have too much to deal now this was not needed during the time Sanji needs to be leader of the crew when luffy and Zoro are away fighting Yonkos. This is why i saw Character regression in him .
