i love trashing the admirals as much as anybody but he would have fully killed momo, yamato, and everyone there until the straw hats actually showed up. yamato hit him with a full conquerors haki strike that made kaido bleed, and aramaki didnt bleed and got right back up. boro breath might look like it did something to a guy who doesnt know how logias work, but it did absolutely nothing. shanks was the only factor that did anything in that fight