What's to be questioned are those two holes that can be used:
- Is Strongest Creature means "regular human" not included?
My headcanon says Human are included BECAUSE the terms used in Japanese is "Saikyō no Seibutsu"..... Believe it or NOT.... another ANIME is using that term.... Which is Baki with "Yujiro Hanma" who is a human and they call him "Strongest Creature" with the same terms "Saikyō no Seibutsu"
In other words, it's a question that can be used for argument against Kaido for people who are foreigners to Japanese Language... but then we see an example from other series where it shows that they consider "human" among "creatures" when describing that title
- Is "World Strongest Creature" describes ONLY physical strength?
This is the hardest question for me.... because there can be argument for both sides...
On one hand, we have a series like Bleach, with Zaraki Kenpachi... Kenpachi stands for "strongest".... in that regard, the character is can truly be considered strongest physically... however he's not strongest when combined with all other abilities in combat regarding that series
On the other hand, in One Piece itself, we have the saying of "if it's 1 vs 1, always bet on Kaido"... this is important because this line ALSO can be used for both sides.... you can take it that this statement basically debunks everything against kaido.... OR, you can use the argument that it's a "BET", a bet is a gamble, so it can result in being FALSE....