Kaido has done so far:
Kaido vs INU + NEKO (SULONG) + KYOSHIRO, ASHURA + KAWAMATSU + KINEMON, O-KIKU, IZOU,
and will probably do: 1 vs Luffy, Zoro, Kid, killer, Law, Sanji, Jimbei, etc ... (although there may be more characters). So after all the confrontation after all this, finally zoro with group work cut kaido and killed him, it doesn't mean that he will be> the strength of the WSC (if not even PK luffy will have the impression of being superior to Kaido in 1v1 the same is true for zoro), replace kaido with zoro in my comment and see if he will replicate all kaido feats in battle, zoro can make 1v9, and then do all 1vs (including luffy, kid and law?)
Apply the same to Shiryu, can he defeat all 9 red scabbards and then fight ZORO, Luffy, Kid, kille, Law, Sanji, jimbei? and give them a lot of work even if they are at a disadvantage?
Obviously not !.