He got pretty nice feats actually, the arc just focused on other things, imagine what Oda would need to do this arc in order to balance things if he put Sanji to beat Cracker/Perospero and then having to raise his bounty close to 1Bi, for Zoro come at Wano with a 320Mi, get hit by crackhead Killer and faint while Sanji trashes a Tobiroppo with his new power up? People would just shit on Zoro nonstop