Could Oda's main purpose for this recent durability boost in Sanji be to "complete" his protective role in the crew? Is it hinting at Sanji's role as we enter endgame territory? Or is it moreso for his future/EOS opponents? Or both?
Sanji now has:
- Base observation haki best in the crew ----> to locate his crewmates at crucial times
- Base speed greatest in the crew ----> to move to his crewmates at immense speed
- Base durability highest in the crew ----> to shield his crewmates from attacks
Add to that his ability for flight, and you have the ultimate guardian.
We're entering the dangerous waters now and Oda has to up the stakes, the antagonists to come have to zero in hard on all of the strawhats, or else Oda is not making it credible. Therefore Sanji himself has to step up.