Rofl what's the excuse for Shanks and Roger not being swordman now, because they don't have a swordstyle, when everytime we see them, they use a fucking sword as their main attack style. And fuck off with the haki shit.
The argument can be said for the like of WB, Big Mom, even Fujitora, since their swords are just a medium to channel their real power. But Roger and Shanks both use swords as their fighting style.
And i'm not even arguing that Mihawk is stronger than Roger and Shanks.