You people remember that Zoro didn't manage to get on the roof on his own, right?
You people remember he and Luffy got YEET'ed back down by Queen?
You people remember he only got to the roof because Marco catapulted him there, right?
Some folks here getting on a high horse of "ZORO GOT ON THE ROOF SO HE DONT WANNA FIGHT KING".
You also remember that, in the end, Queen actually managed to knock out Big Mom, right? Thinking that Zoro would easily make his way upstairs is just delusion. Again.
There's this "powerlevel" delusion that King and Queen are "fodders' compared to Big Mom or Kaido, but they can actually manage to hold their own. Queen immediately went against Big Mom. No fear. So this "Zoro is fighting yonko. no business downgrading and fighting King" is actually just some headcanon stuff you guys decided on your own. Big Mom couldn't finish Marco off, needed Perospero help, and, because he got attacked by the minks, she had to leave Marco alone.
Zoro getting send back down by some attack that destroys the roof and fighting a Calamity back down would not be a downgrade at all.
Calm your "ZOLO IS BUILT DIFFERENT" panties.
Peace.