Outside of this actual fact, what baffles me though is how many people would be "satisfied" by that. Like okay, it's a monumental feat right? But Zoro has barely done anything in the arc regarding major action panels outside of the few he got on the roof.
I think its vital he fights King, not only because it makes sense now with Sanji fighting Queen, but because I feel like after nearly 110 chapters this arc, Zoro hasn't had a proper swordsman fight with amazing clashes and panels.
All we've gotten so far is "how hard can I cut Kaido?" From a basic standpoint. As a fan of Zoro I wasn't satisfied with the rooftop fight, because it only was a measure of Kaido tanking every attack he has.
For context, I wasn't satisfied with Luffy's fight with Kaido UNTIL 1010 when they started clashing with CoC attacks. Before this I disliked the constant blows to Kaido without him doing much.
Tldr: Zoro and Sanji fighting King and Queen is the best outcome because it gives more exposure to the main characters in a 1v1 fight.