The same thing couls be said about Arlong, Baroque Works and Enel. But the Yonko have been hyped for far too long since post Enies Lobby unlike CP9 and Aokiji who appeared just at the same arc. And I am not even putting Vinsmokes and their bomb bracelets on Sanji's wrists.
True in a sense, but you forget they declared war against the entirety of the World Government… and Sanji was there! Considering the whole "balance" the 4 Yonko have with the WG/Shichi's it's hard to just say this hyped up threat now is that much worse than the hyped up threat way back then.
Just fast forwarding the timeline to the Archipelago's the SHs got sweeped by 1 Admiral and some Pacifista's. You get what I'm saying right?
Them back then is definitely comparable to them now. In both cases there should've been faith, and Sanji having been there and throughout the whole journey should know better.
It's fair anyways, Oda is making Sanji out to be somewhat of an idiot just to have a more epic redemption later.