Of course it's impossible to guess exactly where he was prior to Enma, but it gives us a good general idea. If he needs a powerup prior to fighting and defeating a Yonko Commander on his own, then obviously he was below Yonko Commanders before said powerup. You don't give someone a powerup to use against someone if they don't need it.
Isn't Enma mainly for Kaido though? I mean it's not called "the sword that scarred King"... it's the sword that scarred Kaido.
Let me ask, if Zoro uses an attack to reopen Kaido's scar. Won't that same attack be capable of One shotting king?
If Zoro uses 3000 worlds to not only reopen the scar, but then his third sword even creates a new permanent wound in Kaido.
Are you saying that same 3000 worlds won't just one shot King if it lands on him?
And what if Zoro doesn't even use Ashura in any of these fights? What then?
If Post Enma training Zoro can one shot king with 3000 worlds. What's stopping pre Enma Zoro from one shotting King with Ashura?
Of course its possible Ashura has been retconned and Zoro can never use it again but the readers won't see it like that. Unless Oda actually addresses it in the story or in sbs that Ashura will never return, Zoro doing anything to both Kaido and King WITHOUT ASHURA immediately results in questions about what he would do with Ashura.
Of course, this is all speculation. We'll have to wait and see what exactly Zoro does to Kaido but keep in mind, him doing more damage than a bunch of commanders combined can't just be "the sword made him do it"
Zoro can't jump from Veteran level to Admiral level AP just because he got a sword. And I firmly believe that reopening the scar is an admiral level feat.