In Chapter 1001, after executing Rengoku Oni Giri, Zoro said he still needed to draw out more of Enma’s power.
I think a lot of people have been misinterpreting that scene. Whenever Zoro receives a new weapon, he always needs to acclimatise to its use. He is not able to fully maximise the combat potential of the weapon on his first try.
After purchasing his new swords, Zoro decides to test them against the Whiskey Peak Bounty Hunters.
Sandai Kitetsu cuts through more than Zoro wants to, leading him to comment that it’s going to be a problem child.
After receiving Shusui from Ryuma, Zoro decides to test it against Oars.
He comments on the exceptional weight of Shusui.
He then executes his signature 1080 Pound Canon.
The technique became much bigger, with the slash produced by Shusui swallowing the slashes of his other swords.
While the attack was impressive, Zoro noted that it was “too big and slow”. He said that this was proof that he couldn’t fully control the sword yet. Zoro then concluded that the sword would be “a pain to master”.
Zoro’s slashes with Sandai initially cut too deeply. His slashes with Shusui were too big and slow (he may have been putting too much power into his attacks). Perhaps Zoro is currently not putting in enough power in his Enma slashes (to prevent it from draining his Haki).
What happened here with Zoro saying he needs to draw out more of Enma’s power may be similar to the acclimatisation Zoro needed while using Shusui. He’s not fully accustomed to Enma yet, and so he can’t maximise his abilities with Enma. It’s not necessarily the case that Enma is granting Zoro Ryuo.
So the main conclusion that can be drawn at this point is that Zoro has not yet mastered Enma.
I know some people have been debating whether Enma is an “earned power up” and “unearned power up” or “not a power up”, but I’m not particularly interested in that debate. I think that’s a stupid point of contention.