Oda hyped up the grifters since Punk Hazard and introduced a single character to serve as the main plot device to counter these fodders. And yet Kaido and Luffy still have not used their conquerors Haki in order to eliminate all the fodders which makes the whole Tama plot line pointless since conqueror Haki has already been established as fodder control. Oda prefers to drag out arcs than actually providing quality story telling.