AGAIN this is fundamentally an issue you have with Zoro there is clearly downplaying look at your own remarks.
The marines are scared of the Yonko not their commanders.
What makes a Yonko a Yonko ????
Powerful allies (strong commanders)
Territory
an army
The Warlords all have a crew (except Mihawk who Zoro aims to surpass)
Hopefully you can see your own biases in your own argument.
Instead of projecting, you should think about your own biases.
As you can see from my avatar, you can guess who are my favourites in One Piece. My favourite in the crew is Usopp.
WB by himself held the marine, Kaido can clearly solo his crew. Big Mom we could argue.
Among the warlords, Crocodile, Weevil, Blackbeard, Kuma and Mihawk were taken in when they were a solo army. Blackbeard was a no name with a no name crew, but was taken only for his own strength.
Kuma had no interest in capturing Luffy, as he states to Rayleigh when the crew get split. With Zoro we can argue all night why he did that, but at the end he is a revolutionary man. He protected the sunny, he allowed luffy to become strong by saving them.
So no, Zoro did not win because it was not a challenge. What i can say is that Zoro passed a test.
And i am also more zoro than sanji, so please, stop projecting.
Adding to this, Kuma is akin to a professor testing luffy's crew. He saw how strong their trust and alligiqnce was, and since they were not strong enough he sent them where it was best for each. We coulf argue he actually wanted to meet them to understand where was better to send them.