We are speculating anyways so it does not matter if its convincing or not since we could be 100% off anyways lol. I do have a question for you tho. I realized that you might prefer that Zoro has to grow mid fight against Mihawk.
Don't you think its better if he faces him on equal term and its up to the one that surpasses the current limit that Mihawk and Shanks were stuck in?
I am curios i did see many who thinks the same as you do.
First of all, Zombie Ryuma who fought Zoro isn't same who fought Brook, He always hid his True Power
And the same applied on Zoro, cuz we know that his Peak is Asura which He rarely uses
And i'm pretty confident that Mihawk will be the same too, meaning He is hiding his True Max Power
It's a Quality that WSS have (All Three of them)
Even if you go check Ryuma One-Shot (Pre-OP), you will find that He was Out skilled by Cyranno at first but then Demonstrated his True Power which was way way above, so it's a Concept that Oda loves to give Greatest Swordsmen
Since Mihawk is the one who's gonna Power-Up when He fights Zoro (Similar to Zombie Ryuma)
Then that means Zoro will only be ready to face Mihawk, once He surpasses what is normally known about Mihawk (Which is Shanks Level).
And let's be honest, if Oda doesn't give Mihawk the upper hand, then it will look as if it's Mihawk who wants to Defeat Zoro, not Vice Versa
Secondly, Oda must differentiate between the Two in everything, they are Opposites (Knight vs Samurai, Clairvoyant vs Lost, Marine Hunter vs Pirate Hunter, Religious vs Atheist, West vs East, Double-Layered Eyed vs One-Eyed ... etc)
So Oda is gonna make the method in which they reached Level of WSS also Opposites, and since Zoro is all about Willpower which is Self-Made Power, then Mihawk must have achieved his Level thanks to a Power given to him (Hence The Religious Mihawk vs Atheist Zoro)
This is related to a Theory of mine, but i believe those with Double-Layered Eyes are Immortals who transfer into a New Body once their Host dies (Exactly like DFs). An example of that is Hakuba who is most probably an Ancient Super Strong Knight & Master Swordsman whose current Host is Cavendish (Hence why their Power Levels are different despite same Body & Sword, it's cuz Hakuba have more & ancient Experience), and if let's say Cavendish dies, then Hakuba will be reborn in a New Host (Similar to Attack On Titan if you are familiar with it)
When Host & Guest finally Sync & become One, that's when their Eyes turn Double-Layered (It's basically Awakening & those Ancient Guests are like Superior Devils who can directly enter a Human instead of relying on a Fruit & waiting to be consumed)
So Mihawk having those Eyes means He already Synced with Devil inside him gaining Experience of all it's previous Lives, making Mihawk someone who have Experience as if He fought for Hundreds of Years, that's why Defeating him is considered a Mythical Feat, cuz no one can Train or Fight as much as Mihawk in a single life
This is why his name is reference to Dracula and we all know who Dracula is, it also means both Devil & Dragon, He is associated with Cross References a lot (Which indicates Rebirth) & He was even Introduced on top of his Ship which is basically a Coffin, this is also why He speaks in Ancient Tongue (As confirmed by Sandman), it's also why He is extremely Bored & isn't interested in Fighting anymore despite being only in his 40s + Many other Hints ... etc (Just like Vegapunk was born Smart, Big Mom was born Strong, Mihawk was born Skilled, it's cuz there are Methods to preserve certain things for future generation, in Vega's Case they preserved Knowledge, in Big Mom's case they preserved Genes, but in Mihawk's case, they preserved Spirits which also carries on experience & consciousness)
Zoro is only one who can Surpass Mihawk despite only living once because of his Overwhelming Willpower & Spirit, that's why it manifests into a Trio Demon, it's Oda literally giving Zoro an answer to Mihawk's Extra Lives, this way Zoro can triple his Power without the need of living Three times
So in their Final Fight, Zoro must prove that his Self-Made Power, his Willpower can Surpass Mihawk's Power that was gained through years & years & years of stealing experience from others (Oda even hinted at it by making Copy Monkeys be Main Animals on Mihawk's Island, it's to Hint that Mihawk is just like them, a Product of Centuries of Wars & Fights (Mihawk is basically Ultimate Form of those Monkeys that can possibly ever exist)
Sorry for long post, but based on all of this, it means that Zoro cannot reach his Max Power before their Fight starts, cuz it will look as if it was Mihawk who is trying to prove a point, but instead it should be Zoro who proves that Willpower can surpass any Ability, hence why it must be Tested during their Duel, Zoro must reach a point where it looks like it's over & it's point of no return, no second chances (Basically a moment where Mihawk declares having his Clairvoyance can never be surpassed), that's when Zoro will do the impossible & re-forge his Swords using cheer will (Basically each Sword will represent One of his Trion Spirit), and Mihawk will instantly be shocked cuz despite his never-ending experience, He only forged a Single Black Blade, but Zoro forging Three is proof that He finally became Strongest Swordsman Ever Possible & Mihawk will get One-Shot similar to Mr. 1