That just means the alliance would stomp the marines
Admirals are equal to Marco per the databook. Marco and his gang got obliterated by the weakest Yonko. So admirals are far below Yonko.
Aokiji was bleeding from a no name punch from someone that Doflamingo rode like a donkey.
Why do you think Akainu was too scared to send Kizaru to Wano? Because of the same people Kaido has no fear of fighting