He fought Oden, Luffy, Big Mom in one arc. We know he fought in God Valley as well. And most of his flashback we didnt see so he probably fought more people to raise up his reputation, how do you think he got that reputation in the first place if he fought nobody.
Also no top tier really fights other top tier in this show except for Akainu who fought Aokiji, and lately Garp vs Aokiji and Luffy vs Kizaru. The rest just sits in their spot doing next to nothing.
I mean even Mihawk fights nobody, we dont even know how he became WSS and who he fought for it. Last time he fought Shanks was 12 years ago well before Shanks became a top tier himself.
So I feel its unfair to troll Kaido like this when literally almost everyone else does the same.
And lastly he isnt scared of Shanks thats straight up a lie lmao. In fact we never saw him scared of anybody, not even Roger.