@dirtyLarry and others spent yesterday saying Oda cleared everything up regarding Yamato's pronoun in the VC only for the actual chapter to have Kaido call Yamato his son and Luffy calling Yamato a brother lol.
You realize that we knew this for a long time? Really nothing new happened.
We can pretty much assume why Kaido always calls her "son" - he needs a male heir to become shogun. It's not because he's such a progressive and accepting father (like seriously, anyone really thinking he's calling her "son" because he totally accepts her wish has a few screws loose).
As for Luffy - he calls her "Yama-O", which basically translates to "Yama-person". It's often used for males, but in fact it's gender-neutral (just like the "boku" pronoun for example).
Stephen obviously has to take some liberties here to make it sound good for the English audience. "Yamabro" is a lot easier and catchier to read than "Yama-person".
So I don't really understand why you tagged me here, since nothing new happened?
The vivre cards (corrected by Oda himself) and the official promotion are abundantly clear - Yamato should be seen as a cis-woman, which even Artur of all people begrudgingly admited and changed in his reviews.