It’s a little sad, but with the confirmation that this is the final saga, there’s a good chance this is our last recruit. I’ve been thinking that long before saga confirmation though, and with story events as they are, this is a fitting time for the “recruitment phase” of the story to end.
Besides the timing of remaining chapters, two more things suggest this.
1- When Luffy first set out, he specifically mentioned that he needs a crew and that “about 10 men will do”.
Anyway when Luffy said that, it was the beginning of One Piece and Oda thought One Piece would only go for like 5 years right. So we cannot rule out that things may have changed in the meantime.
2- Blackbeard, the man we assume will be our final antagonist, has his crew of 10 Titanic Captains.
The Straw Hats have hit 10 members + Luffy after the addition of Yamato. And now that Luffy is officially a Yonko, his crew in a very symbolic way could be seen as complete. Zoro, Nami, Ussop, Sanji, Chopper, Robin, Franky, Brook, Jimbei, Yamato.
The Straw Hat Pirates’ structure mirroring Blackbeard Pirates’ 10 Titanic Captains would be no coincidence. As most of the fanbase believes, the Straw Hat Pirates and the Blackbeard Pirates will fight for the title of the Pirate King’s crew.