come on, let be serious a guy that has the title of the strongest swordman - clashed with a current Yonko in the past and the clashes that they had were legendary to the point that other Yonkos knew about it. We know that all Yonko have coc.
We know that Zoro aim to defeat Mihawk. We know that Zoro has this power. What else to you need?
Maybe the new film red will give the final proof you need?
That image makes me salty if we don't get to see Zoro vs King wrecking the capital, Zoro vs Fujitora wrecking an island (or Marineford), and Zoro vs Mihawk wrecking the Red Line (my own fanfiction for their place of duel).
Every major 1v1 opponent of Luffy ever since he was revealed to be a Conqueror have been Conquerors - Doflamingo, Katakuri & Kaido. Hody was in an arc meant to hype the strawhats up and Caesar was just part of the bigger arc with Doflamingo.
The same applies to Zoro as well now tbh. I'd be really surprised if his future opponents aren't Conquerors themselves.
it depend on the situation but yeah a sword that try constantly to squis Zoro'ryou doesnt make Zoro fight easyer (which is what a PU is). Yes Zoro will become stronger but you can't denied that something that can cause this to Zoro, due to not pomping enough ryou or losing focus can be call a nerf:
Look is even causing pain to Zoro. Nah this is a nerf especially if the guy that is using the blade hasnt understand yet what the blade want from the user (which after this spoiler we are getting the answer).
Based on that I can argue that Enma was fighint all the time against Zoro which coudnt use his own power as he wanted and also use the fully potential of Enma.
I can agree that Enma is at the same time training indirectly Zoro control of his Ryou at the cost of losing focus and getting exhausted.