Only Luffy and Zoro matter, and Zoro would never forgive himself if he lets himself get knocked out if his captain is out of commission.
It's far too late in the story for Zoro to be cursing his weakness, so we're not going to see Zoro get knocked out.
In general, I think people are too focused on rigid powerscaling. Accept this fundamental truth:
"Characters are as strong as the story requires them to be".
Right now, Luffy is out of commission.
Zoro holds Luffy's life above his own, and even above his dream:
He has unshakeable confidence in Luffy:
If he can't protect his captain, his dream is worthless.
Preskip at Thriller Bark, Zoro was too weak to protect his captain and so he had no choice but to offer up his head instead.
Because of that weakness, Zoro had to lay aside his pride and beg his rival Mihawk to train him:
It is an
insult to Zoro's character for him to allow himself to be defeated, when his captain needs him the most.
- Zoro holds Luffy's life above all.
- He holds fulfilling Luffy's dream above his own ambition.
If Zoro must transcend himself to protect Luffy, then he will. He continue to fight while dead on his feet in order to be able to surpass Mihawk:
Zoro holds Luffy's life even above surpassing Mihawk.
If Zoro gets knocked out while Luffy is out of commission:
- We will get a repeat of Thriller Bark with Zoro cursing his own weakness and inadequacy.
- It would be repetitive character development (essentially redoing Thriller Bark and Sabaody)
- Zoro's training for 2 years with Hawkeyes would be worthless.
- Zoro did not train for 2 years to become stronger so that he may surpass Hawkeyes. He trained for 2 years to become stronger so that he could protect Luffy.
- Failing to protect Luffy when Luffy needs him the most will be a regression for Zoro's character.
The narrative requires that Zoro be strong enough to protect his captain until he recovers, and so Zoro will be.