Luffy would have struggled againt many of Zoro's opponent's ‚ difference is we can make a claim that he would have won at the end‚ he beat whom is stronger for each arc already‚which is a claim we can't make for Zoro ( at the end of each arc ) fighting Luffy's opponents except for Hody
Also Zoro fought morgan and dealt the final blow which was the main villain and also fighting kaido with luffy right now, So its not just hody. I never said that zoros opponents are stronger than luffys opponenets thats not the point.