If you read this for long enough Oda often makes up this shit and characters don't end up doing what they are spewing.
Not true. If it services the plot things this make sense.
- Luffy: "I'm gonna kick Jack's ass one day"
- Ends up being Inu because it makes 100x more sense for Inu to beat Jack for narrative payoff on Zou
Luffy said this once. Yamato has said she's leaving no less than 4 times. Oda has giving Yamato a stupid amount of focus the last 45 chapters. Unique species. Unique devil fruit and powers. Unique fighting style. Unique personality for a female. Beginnings of a flashback. Etc etc etc.
The Scabbards won't be dead post-Wano. They'll all be alive and will serve Momo. Yamato won't be his retainer, they will be. This chapter hard confirmed the mutual-esque strawhat relationship that Luffy gets with his crew.
Franky had this type of moment with Luffy. As did Jinbe when he fought Katakuri. That level of 1 on 1 trust is something Oda only does with Luffy and his crew. Look at how Momo reacts to Onigashima being a bomb this chapter? Look at how Yamato responds to him