Don't confuse toxic fandom with implicit portrayal and facts.
Zoro admitted to it all the way back in Grand Line. First it was alluded vs Crocodile, or rather Zoro feared for Luffys life because he saw himself as equal to Luffy and knew Crocodile was above. Zoro was quite right in his assessment but he didn't count with Will of D, Luffy getting back from certain death twice before winning the third one.
Since then Zoro has acknowledged that Luffy is above. Best example is vs Lucci when Luffy was close to giving up. I think it was Usopp that said something about helping Luffy out, mind you Zoro had enough strength left to fight Marines, but Zoro said out right that's a death ticket. In other words saying only Luffy could deal with Lucci, not even himself was fit for it.
Having said that Zoro does have ambitions, he strives to beat Mihawk which places him in top 10 EoS. Hardly falling of a cliff. But as Mihawk himself said the PKK > WSS. Its not farfetched to expect all of #2-10 can give #1 a great fight, just look at any combat sports, but there can only be one #1 and that will be Luffy.