Reading early Zoro's portrayal, it's baffling to see how much he has regressed in terms of intelligence and level-headness, becoming nearly as stupid as Luffy over the course of the manga.
Same for Sanji who was initially far sweeter and more of a gentleman when dealing with women than the full-blown stupid pervert he would be remembered as, not counting his genuine and strong passion for All Blue.
Pure character flanderization. Plain and simple.
Nowadays whenever Oda has to draw any panel of the Straw Hats its always:
-Luffy being dumb and too joyful
-Zoro being edgy and getting lost
-Sanji being horny
-Usopp being a coward
-Nami and Robin scantly dressed for fanservice
-Chopper used as a cute mascot to sell merch
-Franky, Brook and Jinbei barely existing (because not enough gags to overuse for them)